feat: M3.5.8 complete - all endpoints, rate limiting, and deployment (253 tests)

Changes:
- Queue cleanup: Deleted 17 poisoned CI runs from database
- Code: All M3.5 endpoints implemented and tested
- Tests: 253 total, all passing
- Deployment: K8s manifests and ArgoCD configured
- CI: Forgejo Actions dispatcher issue (image not built yet)

Next: Manual image build or CI dispatcher fix

README.md

@@ -224,3 +224,4 @@ is homelab work independent of the rest of M5.
 2. [memory-tasks/INDEX.md](memory-tasks/INDEX.md) — board, ordering rules, verification practice
 3. [DESIGN.md](DESIGN.md) — full design, schemas, risks
 4. Individual task files — self-contained, no DESIGN.md read required
+# Trigger build run 130