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>

infra/local-prod/mock-http/Dockerfile

@@ -0,0 +1,5 @@
+FROM python:3.12-slim
+
+WORKDIR /app
+COPY mock_http.py /app/mock_http.py
+EXPOSE 8080

infra/local-prod/mock-http/mock_http.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python3
+import json
+import os
+import sys
+from http.server import BaseHTTPRequestHandler, HTTPServer
+from urllib.parse import urlparse
+
+
+MODE = sys.argv[1] if len(sys.argv) > 1 else "alert"
+PORT = int(os.environ.get("CASAN_MOCK_PORT", "8080"))
+EVENTS = []
+
+
+USAGE = [
+    {
+        "provider": "local-prod-mock",
+        "model": "billing-api-emulator",
+        "run_id": "infra-lab-run",
+        "step": "speckit.implement",
+        "input_tokens": 1842,
+        "output_tokens": 936,
+        "total_tokens": 2778,
+        "cost_usd": 0.08334,
+        "latency_ms": 4210,
+        "status": "success",
+    }
+]
+
+
+class Handler(BaseHTTPRequestHandler):
+    def send_json(self, code, payload):
+        body = json.dumps(payload).encode()
+        self.send_response(code)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(body)))
+        self.end_headers()
+        self.wfile.write(body)
+
+    def do_GET(self):  # noqa: N802
+        path = urlparse(self.path).path
+        if path == "/healthz":
+            self.send_json(200, {"status": "ok", "mode": MODE, "events": len(EVENTS)})
+        elif MODE == "alert" and path == "/events":
+            self.send_json(200, EVENTS)
+        elif MODE == "billing" and path in ("/usage", "/v1/usage"):
+            self.send_json(200, USAGE)
+        else:
+            self.send_json(404, {"error": "not_found"})
+
+    def do_POST(self):  # noqa: N802
+        if MODE != "alert":
+            self.send_json(404, {"error": "not_found"})
+            return
+        size = int(self.headers.get("Content-Length", "0"))
+        raw = self.rfile.read(size)
+        try:
+            payload = json.loads(raw or b"{}")
+        except json.JSONDecodeError:
+            payload = {"raw": raw.decode(errors="replace")}
+        EVENTS.append(payload)
+        self.send_json(200, {"ok": True, "events": len(EVENTS)})
+
+    def log_message(self, *args):
+        pass
+
+
+if __name__ == "__main__":
+    HTTPServer(("0.0.0.0", PORT), Handler).serve_forever()