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-sec30-tests.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+set -uo pipefail
+
+# CASAN Plan-16 SEC-30 (X-06) — approval replay prevention (one-time-use nonce).
+#
+# A verified approval (offline signature or IdP JWT) is valid for its whole exp
+# window, so it could be replayed to approve repeatedly. approval-verify now records
+# a per-token nonce and rejects any repeat (in enforced mode / when a nonce ledger
+# is configured). Proves first use is accepted, replay is denied, and dev mode
+# (no ledger) is unchanged.
+#
+# Self-contained: ephemeral reviewer key + committed registry.
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/../scripts/bash/casan-paths.sh"
+PROJECT_ROOT="$CASAN_APP_ROOT"
+S="$CASAN_HARNESS_ROOT/scripts/bash"
+REG="$CASAN_GOVERNANCE_ROOT/reviewers.registry"
+WORK="$(mktemp -d)"; RV="$WORK/reviewers"; mkdir -p "$RV"
+trap 'rm -rf "$WORK"' EXIT
+
+openssl genrsa -out "$WORK/sl.priv" 2048 2>/dev/null
+openssl rsa -in "$WORK/sl.priv" -pubout -out "$RV/security-lead.pub.pem" 2>/dev/null
+printf 'security.strict' > "$WORK/inp"
+bash "$S/approval-sign.sh" policy_change alice "$WORK/inp" security-lead "$WORK/sl.priv" "$WORK/a.sig" >/dev/null 2>&1
+
+export CASAN_REVIEWERS_FILE="$REG" CASAN_REVIEWERS_DIR="$RV"
+
+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 $?; set -e 2>/dev/null || true; }
+
+echo "===== Plan-16 SEC-30: approval replay prevention ====="
+
+# With a nonce ledger configured, the first use is accepted, a replay is denied.
+[[ "$(rc_of env CASAN_APPROVAL_NONCE_FILE="$WORK/nonces.txt" bash "$S/approval-verify.sh" policy_change alice "$WORK/inp" security-lead "$WORK/a.sig")" -eq 0 ]] \
+  && pass "first use of a valid approval accepted" || fail "first use rejected"
+
+[[ "$(rc_of env CASAN_APPROVAL_NONCE_FILE="$WORK/nonces.txt" bash "$S/approval-verify.sh" policy_change alice "$WORK/inp" security-lead "$WORK/a.sig")" -ne 0 ]] \
+  && pass "replay of the same approval DENIED (one-time-use)" || fail "replay accepted"
+
+# Dev default (no ledger, no prod profile): no replay tracking (backward compatible).
+R1="$(rc_of bash "$S/approval-verify.sh" policy_change alice "$WORK/inp" security-lead "$WORK/a.sig")"
+R2="$(rc_of bash "$S/approval-verify.sh" policy_change alice "$WORK/inp" security-lead "$WORK/a.sig")"
+[[ "$R1" -eq 0 && "$R2" -eq 0 ]] \
+  && pass "dev mode: no nonce ledger → replay allowed (backward compatible)" \
+  || fail "dev mode changed (r1=$R1 r2=$R2)"
+
+echo ""
+echo "===== SEC-30 SUMMARY: PASS=$PASS FAIL=$FAIL ====="
+[[ "$FAIL" -eq 0 ]] || exit 1