factory-hygiene row 41 (orthogonal-axes audit) + fork-pr-workflow -1 gotcha

[AceHack]

Summary

Two changes, one PR — causally linked via this session's fork-PR test run (PR #49 landed batch 1 of the speculative drain via the AceHack fork, surfaced both items):

1. FACTORY-HYGIENE row ci: listen on merge_group + document merge-queue plan #41 + BACKLOG P1 row — cadenced audit (every 5-10 rounds) that sweeps the factory's classification axes for overlap. Trigger: Aaron 2026-04-22 explicit ask — "we need to make sure all our axises are orthogonal to the others so there is not overlap ... When all your axes are orthogonal basis covered (meaning they are mutually perpendicular), the set of axes is called an orthogonal basis" + "i guess this is a cadence thing" + "backlog". The rule: every pair of factory classification axes (skill-category, hygiene-scope, persona-surface, cadence-bucket, memory-type, review-target, trust-tier, ...) must be mutually independent. Overlap = rank-reduction and duplicate naming. Distinct from the symmetry audit (row Round 33 — VISION v10: fastest-in-all-classes ambition (OLTP+OLAP+event+cache+streaming) #22): symmetry asks "is A paired with its mirror B?"; orthogonality asks "do axes A and B have zero overlap?"

2. fork-pr-workflow skill — document the -1 suffix gotcha. When gh repo fork is run on a repo that was transferred out of your account, GitHub's 301 redirect record from the pre-transfer namespace reserves the plain name in your account, so gh repo fork silently names your fork <repo>-1. The skill now documents: (a) detection via curl -sI https://github.com/<you>/<repo> showing HTTP 301, (b) recovery via gh repo rename --repo <you>/<repo>-1 <repo> (fork owner can override their own redirect record), (c) confirmation that existing cross-repo PRs continue to work after the rename because GitHub tracks PR head by repo ID not name. This is a contributor-facing UX fix — future contributors hit documented recovery instead of unexpected -1.

Test plan

• markdownlint clean (auto-mode pre-commit passed)
• fork-PR path validated via PR research backfill (batch 1 of 6): land 12 net-new research docs from speculative branch #49 (batch 1 drain merged)
• fork rename from AceHack/Zeta-1 → AceHack/Zeta validated (this PR ships via the renamed fork)
• CI: build-and-test matrix + lints pass on this PR

[Copilot]

Pull request overview

Adds documentation for a new cadenced “orthogonal-axes audit” hygiene item and captures a fork-based contribution workflow edge case where gh repo fork may create <repo>-1 due to a redirect record.

Changes:

• Add FACTORY-HYGIENE row #41 defining an orthogonal-axes audit cadence and outputs.
• Add a P1 BACKLOG item to queue the first orthogonality audit pass + ownership decision.
• Extend the fork-pr-workflow skill to document detection and recovery for gh repo fork -1 suffix forks.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
docs/FACTORY-HYGIENE.md	Adds row #41 describing the orthogonal-axes cadenced audit.
docs/BACKLOG.md	Adds a P1 backlog entry to run/operationalize the orthogonal-axes audit.
.claude/skills/fork-pr-workflow/SKILL.md	Documents the -1 fork-name gotcha plus detection and recovery steps.

[Copilot]

memory/feedback_orthogonal_axes_factory_hygiene.md is referenced as a “durable rule” here, but that file does not exist under memory/ (and docs/FACTORY-HYGIENE.md currently calls it “to be written”). This creates a broken pointer and makes it unclear where the canonical write-up lives. Either add the memory file in this PR or change this reference to match the current state (e.g., mark it as to-be-written / point at the actual existing source-of-truth).

Suggested change

	scope factory). Durable rule in
	`memory/feedback_orthogonal_axes_factory_hygiene.md`. **Work
	queued here:** (a) first audit pass — enumerate current
	factory axes, build pairwise overlap matrix, flag per-pair
	verdicts (collapse / keep-and-document / split); (b)
	scope factory) is the current source of truth; durable
	memory file `memory/feedback_orthogonal_axes_factory_hygiene.md`
	still to be written. **Work queued here:** (a) first audit
	pass — enumerate current factory axes, build pairwise
	overlap matrix, flag per-pair verdicts (collapse /
	keep-and-document / split); (b)