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>

.github/workflows/ci.yml

@@ -0,0 +1,69 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test-backend:
+    name: Backend Tests
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./backend
+    env:
+      DATABASE_URL: file:./test.db
+      JWT_SECRET: test-secret
+      # ANTHROPIC_API_KEY enables the LLM-judge gate; tests skip gracefully when absent
+      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: npm
+          cache-dependency-path: package-lock.json
+
+      - name: Install dependencies
+        working-directory: .
+        run: npm ci
+
+      - name: Setup test database
+        run: npm run db:setup
+
+      - name: Seed test database
+        run: npx prisma db seed
+
+      # Run test files sequentially (--test-concurrency=1) to prevent shared-DB
+      # conflicts between e2e tests that mutate state and services tests that rely on it.
+      - name: Run unit + e2e + LLM-judge tests
+        run: node --import tsx --test-concurrency=1 --test "test/**/*.test.ts"
+
+  test-frontend:
+    name: Frontend Type Check
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: npm
+          cache-dependency-path: package-lock.json
+
+      - name: Install dependencies
+        working-directory: .
+        run: npm ci
+
+      - name: Type check
+        working-directory: ./frontend
+        run: npm test