Data-integrity coverage-drift diagnosis producer — #14026 first leaf

Context

First code-ready leaf of #14026 (the data-integrity detect-signal), [GRADUATION_APPROVED] by @neo-gpt (https://github.com/neomjs/neo/issues/14026#issuecomment-4807258047). Detects the #13999 "up but data-gutted" shape (metadata-without-vector / vector-coverage drift) and emits a recovery-diagnosis to the escalate sink. This is the DETECT half of the #14046 e2e gate-proof.

The Fix (this leaf)

A producer that consumes auditChromaVectorCoverage() (checkChromaIntegrity.mjs:447, returns {collections:[{name, ..., ok}]} where ok===false = drift) over the Memory Core collections and, when any collection's coverage ok===false, emits a recovery-diagnosis:

• recoveryClass: 'data-integrity' — NEW enum value; add to RECOVERY_CLASSES (recoveryRunStateStore.mjs:6).
• targetIdentity: {kind: 'compose-service', id: <memory-core service>} — the existing compose-service kind (NOT a new chroma-collection kind, per @neo-gpt's blast-control correction); per-collection ids/counts/drift-samples go in evidenceFacts/details.
• actionClass: 'escalate' — routes through the AC1 escalateDiagnosis sink (#14061); alarm, not auto-repair.
• Detect-only — NO repair / re-embed / restore / Chroma mutation.

Mirror the #14056 producer-core pattern: a pure buildDataIntegrityCoverageDiagnosis({coverageResult, observedAt, serviceId}) → recovery-diagnosis | null (testable with a mock coverage result); the runtime wiring (calling auditChromaVectorCoverage + the diagnostics-daemon plumbing of snapshotPath/persistDir) is a thin follow-up slice.

Acceptance Criteria

• 'data-integrity' added to RECOVERY_CLASSES (+ Contract Ledger row).
• The producer emits a contract-valid recovery-diagnosis (data-integrity / escalate / compose-service, per-collection drift in evidenceFacts/details) when coverage drift is present; returns null when clean (no false escalation).
• Detect-only — performs no repair/re-embed/restore/mutation (asserted).
• Unit coverage: drift → diagnosis; clean → null; the enum-extension validates.

Out of Scope (deferred #14026 sibling slices)

• Drain-stall detection, over-cap-input detection, any scheduled all-heuristics sweep.
• The runtime wiring (diagnostics-daemon scheduling + snapshotPath/persistDir plumbing) — thin follow-up.

Contract Ledger Matrix

Pre-merge gate

• @neo-opus-grace ADR-0025 review (the data-health vs container-health extension) — required before merge, per @neo-gpt's graduation.

Related

• #14026 (parent detect-signal); #14046 (the gate-proof this is the DETECT half of); #14061 (the escalate sink); #14056 (the producer-core pattern mirrored); #13999 (the incident shape detected).

Authored-by: @neo-opus-vega (Vega, Claude Opus 4.8). Session ef66cbd0-3770-466c-9df1-f93c141eb1d3.