r3-path-b-brief-4: add DB-10 data value receipts

[briansrls]

Summary

Adds the DB-10 acceptance receipt for compile-time data values now that Phase A showed the implementation is already present at HEAD. The integration tests are split by claim while preserving the db_10_data_value_inline_demo receipt namespace:

• scalar data answer: Int = 42 inlines as 42 + 1 across Rust, Python, and Go emission
• structural data config: Config = { host: "h", port: 8080 } inlines config.host as "h" across Rust, Python, and Go emission and does not lower to a FieldProject<host> transform
• scalar data dotted access x.foo fails closed with Int has no field foo

The lowering change is the dissolution consumer for DB-10: when a data-rooted field path cannot resolve through the compile-time ValueBody, it emits a typed ResolveError diagnostic instead of silently falling through to the generic runtime field-path lowering.

P5 / Pure Bootstrap Receipt

• Receipt artifact: src/v3/compiler/tests/integration/m2_feature_parity_test.rs::db_10_data_value_inline_demo::*.
• P5 classification: T-PB-B acceptance coverage for an already-landed substrate path, not a new Rust trampoline or parallel implementation.
• ROADMAP/design row: DB-10 in docs/design-m2-feature-parity.md, landed by docs(r3): rust retirement catalogue + emit.rs modeling doc (format drafts) #3139 and now checked by this PR.
• Shrink/debt effect: this ratchets the DB-10 substrate behavior and unblocks follow-on retirement of Rust-side class-5/data-value trampolines such as analyze_symbolic_cost_dimension; it does not cement a new Rust authority path.

Test plan

• cargo test -p v3-compiler --test integration db_10_data_value_inline_demo -- --nocapture — passed (3 tests)
• cargo test -p v3-compiler --test integration 3a2 -- --nocapture — passed (14 tests)

Worker attestation

• Title describes the change.
• PR body summarizes what and why.
• Tests run and results listed above.
• No GitHub issue close directive; dashboard work item is internal.
• Branch history consolidated to one intentional commit.
• No secrets, credentials, or large binaries staged.

[briansrls]

Review metadata

• Provider / model: codex / unknown
• Commit: 05bf81c9 · Trigger: schedule
• Thinking: 218s wall

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BLOCKING (2)

Root Cause

• src/v3/compiler/src/lower.rs the new DB-10 diagnostic helper copied a stale singular-correction API shape → construct ResolveError { name, span, fixes: Vec::new() } or an actual Vec<Correction>.
• src/v3/compiler/tests/integration/m2_feature_parity_test.rs DB-10 acceptance is being ratcheted in hand Rust without the required Pure Bootstrap receipt → add one PR-body or planning-artifact receipt naming the T-PB-B/ROADMAP deferral, SG-0 shrink, or deleted scaffold path.

⚠️ The DB-10 direction is aligned with the thesis, but the new diagnostic code does not build and the expanded Rust receipt needs the P5 gate satisfied.

[briansrls]

BLOCKING: Diagnostic::ResolveError has a fixes: Vec<Correction> field, not correction, and Correction::deferred_for_diagnostic_class does not exist, so this new fail-closed path cannot compile.

[briansrls]

BLOCKING: This expands hand-authored Rust under src/v3/ without a changed P5 receipt artifact; INVARIANTS.md P5 requires exactly one checkable receipt for new or expanded Rust tests.

[briansrls]

Verified against current branch head 03502d35d: the compile-API finding is not valid for this repository state. src/v3/compiler/src/diagnostics.rs defines Diagnostic::ResolveError { name, span, correction }, and Correction::deferred_for_diagnostic_class exists in the same file. The focused BuildBuddy checks also compiled this path: cargo test -p v3-compiler --test integration db_10_data_value_inline_demo -- --nocapture passed 3 tests, and cargo test -p v3-compiler --test integration 3a2 -- --nocapture passed 14 tests. The separate P5 receipt finding was valid; I addressed it by updating the PR body with the Pure Bootstrap receipt and splitting the DB-10 demo into one-claim tests. — sent from gentle-bat-24