chore: bootstrap repository with governance docs

Initialize git, add Apache-2.0 LICENSE, .gitattributes (LF line
endings), AGENTS.md (entry points, stack, discovery order, baseline
checks), RUNBOOK.md (dev boot, prod deploy with overlay, ingestion,
failures, rollback, scaling notes), .env.prod.example with rotated
credential placeholders, and dev-only warnings on .env.example.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/init_db.py

@@ -0,0 +1,25 @@
+"""Apply Alembic migrations against the configured Postgres."""
+
+from __future__ import annotations
+
+import sys
+from pathlib import Path
+
+from alembic import command
+from alembic.config import Config
+
+from app.config import settings
+
+
+def main() -> int:
+    root = Path(__file__).resolve().parents[1]
+    cfg = Config(str(root / "alembic.ini"))
+    cfg.set_main_option("script_location", str(root / "app" / "db" / "migrations"))
+    cfg.set_main_option("sqlalchemy.url", settings.database_url)
+    command.upgrade(cfg, "head")
+    print("alembic upgrade head: ok")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())