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/tests/phase-sec29-tests.sh

@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+set -uo pipefail
+
+# CASAN Plan-16 SEC-29 (X-05) — audit write fails CLOSED.
+#
+# If the audit log cannot be written (disk full, read-only, quota), a governed
+# action must NOT proceed — there is no action without its accountability record.
+# Proves governance-check denies (and empties the output) when the audit log is
+# unwritable, and still works normally otherwise.
+#
+# Restores the audit log it perturbs on exit.
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/../scripts/bash/casan-paths.sh"
+PROJECT_ROOT="$CASAN_APP_ROOT"
+GC="$CASAN_HARNESS_ROOT/scripts/bash/governance-check.sh"
+AUD="$CASAN_STATE_ROOT/logs/audit/audit.jsonl"
+WORK="$(mktemp -d)"
+export CASAN_AUDIT_KEY_DIR="$WORK/keys"
+
+restore() {
+  [[ -f "$AUD" ]] && chmod 644 "$AUD" 2>/dev/null || true
+  git -C "$PROJECT_ROOT" checkout -- .specify/logs/ .specify/level5/central-governance/ 2>/dev/null || true
+}
+trap 'restore; rm -rf "$WORK"' EXIT
+
+PASS=0; FAIL=0
+pass() { echo "PASS: $1"; PASS=$((PASS + 1)); }
+fail() { echo "FAIL: $1"; FAIL=$((FAIL + 1)); }
+rc_of() { set +e; "$@" >/dev/null 2>&1; echo $?; set -e 2>/dev/null || true; }
+
+echo "===== Plan-16 SEC-29: audit fail-closed when unwritable ====="
+
+echo "benign objective text" > "$WORK/in.txt"
+
+# Normal (writable) path works.
+[[ "$(rc_of bash "$GC" "$WORK/in.txt" "$WORK/ok-out.txt" agent_step)" -eq 0 ]] \
+  && pass "governed action succeeds when audit is writable" || fail "normal governed action failed"
+
+# Make the audit log read-only so the append fails; the action must be denied.
+echo "PREEXISTING_OUTPUT" > "$WORK/blocked-out.txt"
+[[ -f "$AUD" ]] || echo '{}' > "$AUD"
+chmod 444 "$AUD"
+RC="$(rc_of bash "$GC" "$WORK/in.txt" "$WORK/blocked-out.txt" agent_step)"
+chmod 644 "$AUD"
+[[ "$RC" -ne 0 ]] \
+  && pass "unwritable audit → governed action DENIED (fail-closed)" \
+  || fail "action proceeded despite unwritable audit (fail-open)"
+
+[[ ! -s "$WORK/blocked-out.txt" ]] \
+  && pass "output emptied on audit failure (no unaudited output leaks)" \
+  || fail "stale output left after audit failure"
+
+echo ""
+echo "===== SEC-29 SUMMARY: PASS=$PASS FAIL=$FAIL ====="
+[[ "$FAIL" -eq 0 ]] || exit 1