refactor(structure): promote app to repo root + remove redundant workspace cruft

Standard production layout: the OKR app (was nested under AINative_OKR_CASAN5/) is now
the repository root. No more wrapper directory.

- Promote AINative_OKR_CASAN5/* -> repo root (backend/ frontend/ packages/ apps/
  .specify/ docs/ infra/ nginx/ scripts/ + configs). Merge tool dirs: .gitea (kept the
  active deploy ci.yml, added harness-ci.yml + runbooks), .claude (agents/commands +
  launch.json), .github moved up.
- Remove redundant: 00_SUBMISSION_PACKAGE, scattered root notes (FPT_CASAN_Full.md,
  tu-tuong-casan.md, casan-tu-sinh..., casan_harness_assessment.md, source-review...,
  README_CASAN5_REFINED.md), casan-next-plans/ and optimize-docs/ (competition/planning
  artifacts — roadmap + design history preserved in git log / commit messages).
- Update all references to the old layout:
  - .gitea/workflows/{ci,harness-ci}.yml, .github/workflows/{ci,deploy}.yml:
    working-directory .; drop AINative_OKR_CASAN5/ prefix; .specify/{tests,scripts}
    -> packages/casan-harness/... (.specify/logs state kept)
  - .claude/launch.json, .gitea/*-runbook.md: path prefixes
  - CLAUDE.md, README.md: docs/input -> apps/okr/domain/input
  - policy-bundle.yaml: 8 policy paths -> packages/casan-harness/...; manifest re-signed
- secrets-scan.sh: fixture excludes -> new package/domain paths.

Full gate from the new root: PASS=64 FAIL=0 SKIP=3.

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

packages/casan-harness/level5/tool-registry.yaml

@@ -0,0 +1,90 @@
+version: 1.0
+description: CASAN Level 5 tool registry with ownership, schema, risk, idempotency, and rollback metadata
+
+tools:
+  - id: agent_step
+    owner: ai-platform
+    risk_level: low
+    side_effect: false
+    idempotency_required: false
+    timeout_seconds: 600
+
+  - id: write_code
+    owner: engineering
+    risk_level: high
+    side_effect: true
+    idempotency_required: true
+    timeout_seconds: 900
+    allowed_agents: "boss,implement-agent"
+    rollback:
+      strategy: git_patch_reverse
+      script: packages/casan-harness/scripts/bash/rollback-manager.sh
+
+  - id: migration
+    owner: database-owner
+    risk_level: high
+    side_effect: true
+    idempotency_required: true
+    timeout_seconds: 900
+    allowed_agents: "boss,implement-agent"
+    rollback:
+      strategy: migration_down_or_restore
+      script: packages/casan-harness/scripts/bash/rollback-manager.sh
+
+  - id: deploy
+    owner: release-manager
+    risk_level: high
+    side_effect: true
+    idempotency_required: true
+    timeout_seconds: 1200
+    rate_limit_per_run: 2
+    allowed_agents: "boss,release-manager"
+    rollback:
+      strategy: previous_release
+      script: packages/casan-harness/scripts/bash/rollback-manager.sh
+
+  - id: external_api
+    owner: platform-team
+    risk_level: medium
+    side_effect: true
+    idempotency_required: true
+    timeout_seconds: 120
+    allowed_agents: "boss,implement-agent"
+    rollback:
+      strategy: compensating_request
+      script: packages/casan-harness/scripts/bash/rollback-manager.sh
+
+  - id: db_write
+    owner: database-owner
+    risk_level: high
+    side_effect: true
+    idempotency_required: true
+    timeout_seconds: 300
+    allowed_agents: "boss,implement-agent"
+    rollback:
+      strategy: restore_from_backup
+      script: packages/casan-harness/scripts/powershell/rollback-manager.ps1
+
+  - id: write_file
+    owner: engineering
+    risk_level: medium
+    side_effect: true
+    idempotency_required: false
+    timeout_seconds: 60
+    allowed_agents: "boss,implement-agent,design-agent"
+    rollback:
+      strategy: delete_or_restore
+      script: packages/casan-harness/scripts/bash/rollback-manager.sh
+
+level5_gate:
+  required_fields:
+    - id
+    - owner
+    - risk_level
+    - side_effect
+    - idempotency_required
+    - timeout_seconds
+  side_effecting_tools_require:
+    - idempotency_key
+    - audit_record
+    - rollback_strategy