feat(plan-01): Phase 2 — relocate level5/agentops config + init-options to package

Move the harness-config files out of the mixed .specify/level5 and .specify/agentops
dirs (which also hold governance/domain/state) into packages/casan-harness, leaving a
per-file compat symlink at each old path. Runtime state and governance stay in place.

Moved (+ .specify symlink each):
  level5:   drift-policy.yaml kpi-schema.yaml model-fallback.yaml tool-registry.yaml
            harness-package.json project-registry.json provider-usage-sample.json
  agentops: alerts.yaml hallucination-tracking.yaml metrics.yaml rate-limits.yaml tracking.yaml
  top:      init-options.json
Stays in .specify: level5/central-governance (governance), level5/golden-runs (domain,
  Phase 3), agentops/alerts.log (state), traceability-map.json (domain, Phase 3).

Full gate: PASS=64 FAIL=0 SKIP=3 (CASAN_CI_STEP_TIMEOUT_SEC=1200).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

AINative_OKR_CASAN5/packages/casan-harness/level5/model-fallback.yaml

@@ -0,0 +1,33 @@
+version: 1.0
+description: CASAN Level 5 model/tool fallback policy
+
+routes:
+  - step_pattern: "review|test|security"
+    primary: primary-model
+    fallback: verifier-model
+    max_attempts: 2
+    fallback_on:
+      - nonzero_exit
+      - empty_output
+      - timeout
+
+  - step_pattern: "implement|write_code|deploy"
+    primary: primary-model
+    fallback: conservative-model
+    max_attempts: 1
+    fallback_on:
+      - nonzero_exit
+      - policy_reject
+    governance_required: true
+
+default_route:
+  primary: primary-model
+  fallback: fallback-model
+  max_attempts: 2
+  fallback_on:
+    - nonzero_exit
+    - empty_output
+
+evidence:
+  trace_dir: .specify/logs/trace
+  fallback_log: .specify/logs/level5/fallback.jsonl