docs(lost-substrate): full Day-1/2/3 corruption-triage substrate continuation (off-trunk; PR #756 squashed Day-0 only)

docs/lost-substrate/artifacts/2026-04-29-corruption/fsck-extracts.txt

@@ -0,0 +1,89 @@
+# fsck extracts — load-bearing matches with context
+# Source: `git fsck --full --no-progress 2>&1 | grep <obj> -C 5` (reflog-inclusive)
+# Captured 2026-04-29 (Day 3 corruption triage)
+
+## Reflog-inclusive fsck — context for 8d5e67fd
+error: inflate: data stream error (incorrect data check)
+error: corrupt loose object '8d5e67fd313573855848705e4af114f3ff0eecbc'
+error: unable to unpack contents of .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: 8d5e67fd313573855848705e4af114f3ff0eecbc: object corrupt or missing: .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: inflate: data stream error (incorrect data check)
+error: cannot unpack 9bf2daee3ce53c88633824f9532a0158aaa92ed9 from .git/objects/pack/pack-16732bccb3ace9ec45c913c57a1fd050fd730c3f.pack at offset 4973478
+dangling blob 1f003ef9077ba9779af779c18efa3ff5a6f39470
+dangling commit 2a00a9f5168ddfd359f62f2e274cb768159f9014
+dangling blob e20172cea3dd96f93dc3004d5ebc7eb137693701
+--
+dangling commit 795b1d3a5b7c5379cd6a1ad8419f0a5e9535c476
+dangling commit b55b5628445f31bb2f1df636859915daef5be582
+dangling tree f65bb21a7409dcdadb9ee6e8f02f1c0d07c93a96
+dangling commit 6e5c40364b078f5a947bf79d9cc9540c3ae940e7
+dangling tree ba5cc0356d2b571ba19477f5be8c16e15993faf6
+missing blob 8d5e67fd313573855848705e4af114f3ff0eecbc
+dangling commit 385f12ddc72e05da9be752c5a5acc53ba472bb90
+dangling commit c95f5c65cbae62fd249fedb38c9e45d59260d061
+dangling tree 78606cccb9ba0693d61a3cad81d71b05727ddf2f
+dangling commit a1605b88ddb8dd3543610235c585b1372f1eaba4
+dangling commit f5609f368a7e17ba22224eec4bbc715ba3c6f4dc
+
+## Reflog-inclusive fsck — context for 9bf2daee
+error: inflate: data stream error (incorrect data check)
+error: corrupt loose object '8d5e67fd313573855848705e4af114f3ff0eecbc'
+error: unable to unpack contents of .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: 8d5e67fd313573855848705e4af114f3ff0eecbc: object corrupt or missing: .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: inflate: data stream error (incorrect data check)
+error: cannot unpack 9bf2daee3ce53c88633824f9532a0158aaa92ed9 from .git/objects/pack/pack-16732bccb3ace9ec45c913c57a1fd050fd730c3f.pack at offset 4973478
+dangling blob 1f003ef9077ba9779af779c18efa3ff5a6f39470
+dangling commit 2a00a9f5168ddfd359f62f2e274cb768159f9014
+dangling blob e20172cea3dd96f93dc3004d5ebc7eb137693701
+dangling tree fa019e9576ad659d4a75caf4599d831ee4df415b
+dangling tree 490275af8f57e4fac5e77d026c4b47f97e81bf27
+
+## --no-reflogs fsck — context for 8d5e67fd
+error: inflate: data stream error (incorrect data check)
+error: corrupt loose object '8d5e67fd313573855848705e4af114f3ff0eecbc'
+error: unable to unpack contents of .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: 8d5e67fd313573855848705e4af114f3ff0eecbc: object corrupt or missing: .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: inflate: data stream error (incorrect data check)
+error: cannot unpack 9bf2daee3ce53c88633824f9532a0158aaa92ed9 from .git/objects/pack/pack-16732bccb3ace9ec45c913c57a1fd050fd730c3f.pack at offset 4973478
+dangling blob 1f003ef9077ba9779af779c18efa3ff5a6f39470
+dangling commit 2a00a9f5168ddfd359f62f2e274cb768159f9014
+dangling commit 9f01f442e7362a9efcd6fc7b1c87fed41eb4146f
+--
+dangling tree f65bb21a7409dcdadb9ee6e8f02f1c0d07c93a96
+dangling commit 6e5c40364b078f5a947bf79d9cc9540c3ae940e7
+dangling commit 8d5ca82de7eaa851a12c952ef9ae162ee675581a
+dangling tree ba5cc0356d2b571ba19477f5be8c16e15993faf6
+dangling commit 9d5db210aee2b017e99c8d2c78f77242fb24ec0b
+missing blob 8d5e67fd313573855848705e4af114f3ff0eecbc
+dangling commit be5ed39f8f223aac1149a287fa8f24e3a94c52ae
+dangling commit e15e99645306000c5f9d6ee549b8bdff88069a71
+dangling commit fc5ec3b3552af63e82f8f9992a3d1fdcd7931c6e
+dangling commit 145ff57c8a073d0fc8ff11dece9ac7e492c85adc
+dangling commit 255ff59fc67565e9be345b810aa2b784360c7887
+
+## --no-reflogs fsck — context for 9bf2daee
+error: inflate: data stream error (incorrect data check)
+error: corrupt loose object '8d5e67fd313573855848705e4af114f3ff0eecbc'
+error: unable to unpack contents of .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: 8d5e67fd313573855848705e4af114f3ff0eecbc: object corrupt or missing: .git/objects/8d/5e67fd313573855848705e4af114f3ff0eecbc
+error: inflate: data stream error (incorrect data check)
+error: cannot unpack 9bf2daee3ce53c88633824f9532a0158aaa92ed9 from .git/objects/pack/pack-16732bccb3ace9ec45c913c57a1fd050fd730c3f.pack at offset 4973478
+dangling blob 1f003ef9077ba9779af779c18efa3ff5a6f39470
+dangling commit 2a00a9f5168ddfd359f62f2e274cb768159f9014
+dangling commit 9f01f442e7362a9efcd6fc7b1c87fed41eb4146f
+dangling blob e20172cea3dd96f93dc3004d5ebc7eb137693701
+dangling commit e5019d81cf9d549bfeee9c6751f7c8d5911af94f
+
+## Connectivity-only fsck — context for 8d5e67fd
+(no match)
+
+## Connectivity-only fsck — context for 9bf2daee
+(no match)
+
+## Mode-comparison summary
+fsck-full (reflog-inclusive)        line count:      627
+fsck-full-no-reflogs                line count:     1116
+fsck-connectivity                   line count:      620
+
+(Mode-dependent reachability: --no-reflogs reports MORE objects as
+ dangling because reflog-tip commits no longer count as reachable.)

docs/lost-substrate/artifacts/2026-04-29-corruption/git-gc-config.txt

@@ -0,0 +1,13 @@
+# git gc + rerere config snapshot — 2026-04-29 corruption triage
+# (read-only inspection; no mutation)
+
+git version              = git version 2.54.0
+
+gc.auto                  = (unset; default ~6700)
+gc.autoPackLimit         = (unset; default 50)
+gc.pruneExpire           = (unset; default 2.weeks.ago)
+gc.reflogExpire          = (unset; default 90.days.ago)
+gc.reflogExpireUnreachable = (unset; default 30.days.ago)
+gc.worktreePruneExpire   = (unset; default 3.months.ago)
+gc.rerereResolved        = (unset; default 60.days)
+gc.rerereUnresolved      = (unset; default 15.days)

docs/lost-substrate/artifacts/2026-04-29-corruption/hour-05Z-ls-remote.txt

@@ -0,0 +1,10 @@
+# git ls-remote --heads origin chore/heartbeat-batch-2026-04-26-hour-05Z
+# Captured 2026-04-29 (Day 3 corruption triage)
+#
+# Result: empty (no output below this header).
+#
+# Empty output proves origin no longer has the branch
+# `refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z`.
+# The same-named local remote-tracking ref under
+# `refs/remotes/origin/chore/heartbeat-batch-2026-04-26-hour-05Z`
+# is therefore stale (preserved evidence, not origin recovery).

docs/lost-substrate/artifacts/2026-04-29-corruption/hour-05Z-show-ref.txt

@@ -0,0 +1,2 @@
+d9feb3f08603e37118491e26527c03e6e5760d5b refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z
+d9feb3f08603e37118491e26527c03e6e5760d5b refs/remotes/origin/chore/heartbeat-batch-2026-04-26-hour-05Z

docs/lost-substrate/artifacts/2026-04-29-corruption/rev-list-extracts.txt

@@ -0,0 +1,9 @@
+# rev-list extracts — load-bearing matches only
+# Source: `git rev-list --objects --all | grep <obj>`
+# Captured 2026-04-29 (Day 3 corruption triage)
+
+## Matches for 8d5e67fd313573855848705e4af114f3ff0eecbc
+8d5e67fd313573855848705e4af114f3ff0eecbc docs/hygiene-history/loop-tick-history.md
+
+## Matches for 9bf2daee3ce53c88633824f9532a0158aaa92ed9
+9bf2daee3ce53c88633824f9532a0158aaa92ed9 docs/category-theory/ctfp-milewski.pdf

docs/lost-substrate/artifacts/2026-04-29-corruption/triage-report.md

@@ -0,0 +1,220 @@
+# Corruption triage — 2026-04-29 — empirical artifact
+
+This file captures the exact commands run, the raw outputs (in
+sibling files), and the conclusion drawn. It exists so a future
+reader can verify the prose conclusions in the ledger against the
+artifacts, rather than trusting the summary.
+
+## Sibling artifact files (load-bearing extracts only)
+
+Per Aaron 2026-04-29 (the repo is the soulfile — keep it
+clean): only the **load-bearing extracts** are committed,
+not the raw multi-MB diagnostic dumps. The grep recipes that
+produce these extracts are below; future readers can re-run
+locally to regenerate the raw outputs if needed.
+
+| File | Source command (extract-recipe in re-run section) |
+|---|---|
+| `fsck-extracts.txt` | grep -C 5 of corrupt SHAs against `git fsck` outputs in three modes (reflog-inclusive / `--no-reflogs` / `--connectivity-only`) plus per-mode line-counts to evidence mode-dependence |
+| `rev-list-extracts.txt` | grep of corrupt SHAs against `git rev-list --objects --all` |
+| `git-gc-config.txt` | git version + per-key `git config --get gc.*` + `gc.rerereResolved` / `gc.rerereUnresolved` snapshot |
+| `hour-05Z-show-ref.txt` | `git show-ref \| grep hour-05Z` |
+| `hour-05Z-ls-remote.txt` | `git ls-remote --heads origin hour-05Z` (empty = origin no longer has the branch) |
+
+All files are point-in-time evidence; do not edit.
+
+### Re-run recipe (regenerates raw outputs locally)
+
+If a future reader wants the raw multi-MB dumps (this file
+intentionally does not commit them — see Aaron's
+soulfile-cleanliness rule), run from repo root:
+
+```bash
+mkdir -p /tmp/corruption-triage-raw
+git fsck --full --no-progress              > /tmp/corruption-triage-raw/fsck-full.txt 2>&1
+git fsck --full --no-reflogs --no-progress > /tmp/corruption-triage-raw/fsck-full-no-reflogs.txt 2>&1
+git fsck --connectivity-only --no-progress > /tmp/corruption-triage-raw/fsck-connectivity.txt 2>&1
+git rev-list --objects --all               > /tmp/corruption-triage-raw/rev-list-all-objects.txt 2>&1
+ls -la /tmp/corruption-triage-raw/
+```
+
+The raw outputs are reproducible from any clone with the same
+local refs at the same point in time. Committing the extracts
+preserves the load-bearing evidence; committing the raw dumps
+would dirty the soulfile.
+
+## Two corrupt objects under triage
+
+| SHA | Type | Size | Source path |
+|---|---|---|---|
+| `9bf2daee3ce53c88633824f9532a0158aaa92ed9` | blob (recovered from origin) | 16,455,417 bytes | unknown — large blob |
+| `8d5e67fd313573855848705e4af114f3ff0eecbc` | blob (corrupt loose, locally) | unrecoverable from origin | `docs/hygiene-history/loop-tick-history.md` (intermediate version) |
+
+## Three-bucket reachability — `8d5e67fd`
+
+Per Amara 2026-04-29: `git fsck` reachability is mode-dependent
+(reflog-inclusive vs `--no-reflogs`). A correct classification
+distinguishes three buckets:
+
+| Bucket | Definition | Verdict for `8d5e67fd` |
+|---|---|---|
+| A | Live branch / tag / ref reachable | **YES** — `refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z` reaches it (local-only; the same-named remote-tracking ref is stale — origin no longer has the branch) |
+| B | Reflog / stash / local-recovery reachable | Indeterminate from this scan; reflog scan was reflog-inclusive fsck (showed dangling adjacency); `refs/stash` is empty |
+| C | Dangling / unreachable only | **NO** — bucket A applies, so C does not |
+
+### Verifying bucket A
+
+```text
+$ git rev-list --objects --all | grep 8d5e67fd
+8d5e67fd313573855848705e4af114f3ff0eecbc docs/hygiene-history/loop-tick-history.md
+
+$ git for-each-ref ... | per-ref rev-list grep
+ref=refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z   → reaches it
+ref=refs/remotes/origin/chore/heartbeat-batch-2026-04-26-hour-05Z → reaches it (stale)
+```
+
+### Verifying the remote-tracking ref is stale
+
+```text
+$ git ls-remote origin refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z
+(empty — origin no longer has this branch)
+
+$ git clone --no-checkout --quiet \
+    --branch chore/heartbeat-batch-2026-04-26-hour-05Z \
+    https://github.com/Lucent-Financial-Group/Zeta.git \
+    /tmp/repo-fresh-corruption-recheck-2026-04-29
+fatal: Remote branch chore/heartbeat-batch-2026-04-26-hour-05Z not found in upstream origin
+```
+
+### Content-equivalence verification — `8d5e67fd`
+
+Per Amara's correction: verify squash-preservation by **content**,
+not by ancestry vibe.
+
+```text
+$ BR=refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z
+$ OBJ=8d5e67fd313573855848705e4af114f3ff0eecbc
+
+$ git ls-tree -r "$BR" | grep "$OBJ"
+(no path-match — corrupt blob is NOT at the branch tip)
+
+$ git show "$BR":docs/hygiene-history/loop-tick-history.md | head -1
+# Loop-tick history          ← branch tip's tick-history.md is readable
+
+$ git diff --name-status origin/main..."$BR" \
+    -- docs/hygiene-history/loop-tick-history.md
+M docs/hygiene-history/loop-tick-history.md   ← diff succeeds
+
+$ git log --oneline -1 "$BR"
+d9feb3f chore(loop-tick-history): hour-05Z bundle close 2026-04-26T05:59:36Z ...
+```
+
+**Branch tip is clean.** The corrupt blob `8d5e67fd` is from
+the branch's **intermediate history** (an earlier commit on the
+same branch path), NOT the current tip. The branch is also NOT
+an ancestor of `main` (its tip is post-squash-merge and
+abandoned), and `main` carries the equivalent content under a
+different blob (`de670f72d6fd34208d04863818288d764150a151`).
+
+```text
+main's tick-history blob: de670f72d6fd34208d04863818288d764150a151
+branch-tip's blob:        (different, clean — readable via git show)
+corrupt blob:             8d5e67fd313573855848705e4af114f3ff0eecbc
+                          ← appears only in intermediate history
+```
+
+## Final classification — `8d5e67fd`
+
+```text
+CORRUPT_BLOB_REFERENCED_BY_LIVE_LOCAL_BRANCH_AND_STALE_REMOTE_TRACKING_REF
+```
+
+(sub-bucket of bucket A under the three-bucket schema; refined
+sub-condition: branch TIP is clean, corrupt blob is in
+intermediate history of the branch only.)
+
+Substrate-loss assessment:
+
+- **Current-state use** (checkout / hard-reset-to-tip / diff vs
+  main): zero impact. Branch tip and main are both readable.
+- **Bisect-through-pre-merge-history**: impacted. Bisecting
+  `loop-tick-history.md` through this branch's intermediate
+  revisions would surface the corrupt blob; that pre-merge
+  bisect-step granularity is the only thing actually lost,
+  and it's a niche use case for a stale post-merge local
+  branch.
+
+## Hard-reset readiness — qualified statement
+
+```text
+This corruption does not appear to affect current main, but it
+DOES affect at least one live local branch (specifically, the
+intermediate history of refs/heads/chore/heartbeat-batch-2026-
+04-26-hour-05Z). Hard reset / branch cleanup remains blocked
+until the branch's content is classified as preserved,
+obsolete, or explicitly abandoned.
+```
+
+Branch-tip checkout / hard-reset-to-tip is fine. Reading
+intermediate-history blobs would surface the corruption.
+
+## Stale remote-tracking ref — evidence, not origin recovery
+
+```text
+$ git show-ref | grep 'chore/heartbeat-batch-2026-04-26-hour-05Z'
+d9feb3f08603e37118491e26527c03e6e5760d5b refs/heads/chore/heartbeat-batch-2026-04-26-hour-05Z
+d9feb3f08603e37118491e26527c03e6e5760d5b refs/remotes/origin/chore/heartbeat-batch-2026-04-26-hour-05Z
+                                         ↑ same SHA → ref is stale, not authoritative
+
+$ git ls-remote --heads origin chore/heartbeat-batch-2026-04-26-hour-05Z
+(empty — origin no longer has this branch)
+```
+
+The remote-tracking ref is **stale** — origin deleted the
+branch (presumably after squash-merge), but the local repo
+still carries the same-named ref under
+`refs/remotes/origin/...`. This stale ref is evidence about
+the prior state of origin; it is NOT proof origin currently
+has the object. Do not prune it during triage — `git fetch
+--prune origin` and `git remote prune` would remove it, and
+that's a destructive cleanup decision under the same rule as
+GC.
+
+```text
+Stale remote-tracking ref is evidence, not origin recovery.
+Do not prune it while investigating lost substrate.
+```
+
+## Cleanup posture
+
+```text
+Cleanup is a destructive decision, not a repair step.
+```
+
+`git gc` / `git prune` / `git repack -Ad` / `git fsck --lost-found`
+remain forbidden during triage. Auto-gc thresholds are at default
+(per `gc-config-snapshot.txt`); below-threshold loose-object count
+means auto-gc is not imminent, but the discipline is "no implicit
+cleanup decision" not "we have time."
+
+A future cleanup may remove this unreachable/corrupt evidence, so
+cleanup must wait until related dangling/reflog/stash surfaces
+are classified and either preserved or explicitly abandoned.
+
+## Composes with
+
+- `docs/lost-substrate/inventory-ledger-2026-04-29.md` — the
+  inventory ledger that surfaced these findings.
+- `memory/feedback_corruption_triage_discipline_object_health_incident_aaron_amara_2026_04_29.md`
+  — the durable discipline rule.
+
+## Distilled keepers (Amara 2026-04-29)
+
+```text
+A corrupt object is not a backlog item — it is a substrate health incident.
+Do not prune the evidence while investigating lost evidence.
+Recoverable-from-origin requires fresh-clone cat-file type + size verification.
+Cleanup is a destructive decision, not a repair step.
+Corruption lane means exclusive lane.
+If corruption is the incident, everything else is noise.
+```