feat(resilience-and-recovery): add resilience-and-recovery skill (#223)

Add the resilience-and-recovery skill for designing, exercising, and
evidencing graceful degradation, disaster recovery, and restoration
behavior across systems and dependencies.

- SKILL.md with both resilience patterns (graceful degradation and
  restore-based recovery), exercise-evidence requirement, HA vs
  recoverability distinction, context-dependent RTO/RPO, and
  structured plan-template fields
- README.md with all five required human-facing sections
- 7 reference files covering failure modes, recovery plan template,
  exercise design, RTO/RPO decision record, data integrity
  verification, recovery communication, and follow-up work ledger
- 1 bounded discovery brief surveying SRE, platform, data, security,
  release, and incident-learning
- 5 output-quality eval cases covering dependency outage, restore
  test, regional failure, degraded-but-available path, and recovery
  exercise with unowned gap escalation
- Routing to site-reliability-engineering, platform-engineering,
  data-engineering, secure-software-engineering, release-engineering,
  and incident-learning; feeds production-excellence bundle
- Root README catalog entry, skill-triggers index, and regenerated
  marketplace/Codex/llms.txt catalogs

Co-authored-by: username <username>
Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

.claude-plugin/marketplace.json

@@ -806,6 +806,15 @@
       "strict": false,
       "description": "Plan, conduct, evaluate, and synthesize rigorous research. Use for journalistic, industry, or technical investigations that need credible evidence and a traceable method."
     },
+    {
+      "name": "resilience-and-recovery",
+      "source": "./",
+      "skills": [
+        "./resilience-and-recovery"
+      ],
+      "strict": false,
+      "description": "Design, exercise, and evidence graceful degradation, disaster recovery, and restoration behavior across systems and dependencies. Covers failure-mode analysis, RTO/RPO decision records, restore testing, game days, failover drills, data integrity verification, and recovery communication. Do not use for live incident command or incident response; route to site-reliability-engineering for those. Do not use for infrastructure implementation details; route to platform-engineering."
+    },
     {
       "name": "restic",
       "source": "./",