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/scripts/bash/guideH4-H5-H6.md

@@ -0,0 +1,25 @@
+INPUT
+  ↓
+security-check.sh input   (H4: prompt injection, PII, secret)
+  ↓
+governance-check.sh       (H5: risk, approval, hash-chain audit)
+  ↓
+agent-metrics.sh          (H6: latency, tokens, cost, retry, status, alert)
+  ↓
+security-check.sh output  (H4: output redaction/filter)
+  ↓
+OUTPUT
+  ↓
+LOG + TRACE + METRICS + AUDIT
+
+Unified wrapper:
+
+```bash
+.specify/scripts/bash/casan-harness.sh input.txt output.txt agent_step
+```
+
+Verification:
+
+```bash
+bash .specify/tests/run-casan4-harness-tests.sh
+```