refactor(db): move git registry store ownership

[TheSentinel454]

Current reconstructed head

Exact base: codex/issue-2-moderation-store at a0a4afc5317bb15e02f77a169ca359e8af289e28
Exact head: codex/issue-2-git-repo-store at dc73defc41030278821ce43478bbb222226141e7

This current head removes crates/buzz-db/tests/store_ownership.rs; no replacement path-sensitive ownership test is introduced. Apart from removing that complete test-file diff, the production patch is byte-for-byte identical to the previously reviewed slice. This remains part of tracker #2 and the #17/#19 acceptance work.

Independent exact-head review from a separate clean Blox workstation found no issues. Current-head evidence passed formatting, strict buzz-db clippy, 111 non-PostgreSQL library tests with 200 PostgreSQL tests ignored, the observability source test, relay consumer compilation, exact ownership/unique-span review checks, and 4 Git-registry PostgreSQL tests on native PostgreSQL where applicable.

Summary

Continue tracker #2 by making git_repo.rs own the Git repository-name registry persistence boundary. ReserveOutcome, the SQL implementation, and focused PostgreSQL tests already lived there; this child moves the remaining four Db methods and datastore spans out of lib.rs without changing public signatures or behavior.

This also advances #17 and #19 through single test and span ownership.

Stack

• Tracker: TheSentinel454/buzz#2
• Test ownership acceptance: #17
• Span ownership acceptance: #19
• Exact base: codex/issue-2-moderation-store at f87152c (#6808)
• Exact head: codex/issue-2-git-repo-store at 3f651b7

Domain moved

• Repository-name owner lookup, reservation, per-owner count, and release facades
• All four existing fixed-name PostgreSQL datastore spans

crates/buzz-db/src/lib.rs falls from 4,033 to 3,985 lines.

Non-goals

• Git object storage, manifest, transport, policy, or relay behavior
• Registry SQL, quota, reservation race, rollback, schema, locking, transaction, retry, timeout, or client-visible behavior changes
• Generic store traits, raw pool access, executor migration, or crate reorganization

Risk

Small review surface and low semantic risk. The four facades and spans moved intact and call the same module-owned functions with the same pool, arguments, and return types. Existing SQL and focused tests are unchanged. The only extra source line is a secret-scanner suppression on the long-standing fake local test URL in the now-modified module.

Blox verification

Author workstation: buzz-tornquist-issue-2-store-stack (2046520), exact head c3ece0f59aebb6119cb0d942b614fe2d3dce35d4.

• cargo fmt --all --check
• git diff --check 5fd23b4bd81d9db24c2ac4ad29a7ff74590de700..HEAD
• cargo clippy -p buzz-db --all-targets -- -D warnings
• cargo clippy -p buzz-relay --all-targets -- -D warnings
• cargo test -p buzz-db --lib: 108 passed, 200 ignored
• cargo test -p buzz-db --test observability_source: 1 passed
• Native PostgreSQL 17.11, migrations 1–32 already applied: all 4 Git-registry PostgreSQL tests passed
• cargo test -p buzz-relay --lib: 909 passed, 48 ignored
• Signed commit hooks passed without bypass

Independent exact-head Blox review: no findings. Review artifacts were preserved before teardown.

Remaining tracker work

Next: archived identities, then usage/admin/maintenance, deletion ownership, and the final runtime-boundary/test audit.

Superseded pre-comment restack verification

PR #6700 merged before publication completed. This layer was restacked onto current main through the exact parent named above; the final cumulative tip is 2ddcc8a. Cumulative author gates passed: formatting and diff checks; buzz-db and buzz-relay all-target clippy with -D warnings; DB lib 111 passed / 200 ignored; ownership 22/22; observability 1/1; the full isolated PostgreSQL domain matrix; and relay lib 910 passed / 49 ignored.

Result

No findings.

Exact revision and isolation

• Base: da6d86cb4f46504edd3d860571e670d07b2f2023
• Head: 6ab8bc04429d6596c91bcfc0bcf150f69ab2d17f
• Verified head parent and merge-base: exact base above
• Reviewer workstation: buzz-tornquist-pr-6809-final-review (2057664)

The fresh shallow workstation was clean and unclaimed, had no competing commands, and had no Buzz production relay credentials or ownership-report file.

Review conclusions

• The repo-owner lookup, reservation, quota count, and owner-scoped release facades move intact into git_repo.rs.
• Reservation/collision/idempotency SQL and community scoping are unchanged. Each public logical operation retains one fixed-label datastore span.

Verification

• Diff check and Rust formatting: passed.
• Buzz DB and relay all-target clippy with -D warnings: passed.
• Buzz DB library: 111 passed, 200 ignored.
• Native PostgreSQL 17.11, migrations complete: all four git-repository tests passed.
• Final detached head remained clean; no duplicate datastore-span names were found.

Artifacts: pr-6809-final-review-artifacts.tgz, SHA-256 d389bffa772b51c34f8b4345d5fa4d200dfa32d9020a967505eccea72b1e38dc. Archive and internal checksums were verified locally.

Comment-addressed restack

Review follow-up on #6777 removed only the low-value replaceable ownership source test. This PR was restacked onto its rewritten parent; its production patch is unchanged.

• Exact base: f87152c1c0d3f9ab460e5b54711af41b43da0e28
• Exact head: 3f651b72d81ca6d6d051200c9384e189e36aeaf2
• Final cumulative tip: 6fa2f104d42c6ba85bdf62e7ccb74ceaf4a84f67
• Per-layer patch-ID and tree audits confirm this PR’s production diff is unchanged from its pre-comment head.
• Cumulative Blox gate: formatting and diff checks; strict buzz-db/buzz-relay Clippy; DB lib 111 passed / 200 ignored; ownership 21/21; observability 1/1; every moved PostgreSQL test; relay lib 910 passed / 49 ignored.
• Independent re-review at this exact head: no findings; fresh exact-parent/head Blox review passed fmt/diff, strict buzz-db/buzz-relay Clippy, DB lib and current ownership/observability/unique-span guards, 4 Git-registry PostgreSQL tests, and relay compilation.