feat(graph): introduce graph.inspect.v1 contract and schema for SBOM relationships

- Added graph.inspect.v1 documentation outlining payload structure and determinism rules.
- Created JSON schema for graph.inspect.v1 to enforce payload validation.
- Defined mapping rules for graph relationships, advisories, and VEX statements.

feat(notifications): establish remediation blueprint for gaps NR1-NR10

- Documented requirements, evidence, and tests for Notifier runtime.
- Specified deliverables and next steps for addressing identified gaps.

docs(notifications): organize operations and schemas documentation

- Created README files for operations, schemas, and security notes to clarify deliverables and policies.

feat(advisory): implement PostgreSQL caching for Link-Not-Merge linksets

- Created database schema for advisory linkset cache.
- Developed repository for managing advisory linkset cache operations.
- Added tests to ensure correct functionality of the AdvisoryLinksetCacheRepository.

docs/product-advisories/ADVISORY_INDEX.md

@@ -415,7 +415,7 @@ These are the authoritative advisories to reference for implementation:
   - SPRINT_0172_0001_0003_notify_ack_tokens.md
 - **Related Docs:**
   - `docs/modules/notify/architecture.md` - Module architecture
-- **Gaps:** `31-Nov-2025 FINDINGS.md` (NR1–NR10 remediation task NOTIFY-GAPS-171-014)
+- **Gaps:** `31-Nov-2025 FINDINGS.md` (NR1–NR10 remediation task NOTIFY-GAPS-171-014; blueprint `docs/notifications/gaps-nr1-nr10.md`)
 - **Status:** Fills MEDIUM-priority gap - covers rules engine, channels, noise control, ack tokens
 
 ### Graph Analytics & Dependency Insights