lisa/feat/bch-1309-core-suggestion-engine

[ccf-lisa]

automated implementation by lisa.

[gusfcarvalho]

Findings inline. The lint blocker from the previous HEAD is already fixed by fc928e7 (lint now green), so this round drops it. Remaining: one Medium determinism issue (gather.go SampleTitles arbitrary subset — the pass-4 self-review note that's still open), plus Low/nit items (unstable accept tie-break, uncorrelated control_implementations join, UTF-8-unsafe byte truncation, an apparently-unused VisibleFilters field). Nice work — the canonical-hash dedupe, advisory-lock concurrency guard, and SSP-isolation paths are all well-covered by tests.

[gusfcarvalho]

Approving. Commit 206848a resolves all findings from the prior round, each with a regression test, and CI is fully green (lint, unit, integration, check-diff):

• SampleTitles determinism — now accumulates all titles then sorts/dedupes/caps to 3 (integration test asserts a stable subset).
• Accept tie-break — secondary keys are now ProposedFilterName then suggestion ID.
• control_implementations — replaced the uncorrelated join with a correlated LATERAL aggregate, so duplicate/empty implementations can't shadow the real text (covered by a new integration test).
• UTF-8 truncation — shared rune-aware truncateRunes helper across all four sites (unit tests confirm valid UTF-8 + exact rune counts).

Verified locally: build, vet, golangci-lint (0 issues), go test and gofmt all clean. Nice work.

[ccf-lisa]

PR approved. Marking as ready for e2e.