§22.13 step 1: default-project-id re-stamp (v0.39.0)

projects.restamp_default_project(config): at startup after the registry mirror,
renames project_id from the M1 bootstrap 'default' to the configured
DEFAULT_PROJECT_ID across every project-scoped table (discovered by column) and
drops the stale 'default' projects row, so a deployment's original corpus lands
at a meaningful /p/<id>/ and 'default' is never a public URL. FK off for the
rename (parent+children move together) + foreign_key_check backstop. Idempotent;
no-op unless DEFAULT_PROJECT_ID is set to a non-'default' value.

test_restamp_default_project.py (3 tests). 450 backend green.

This is the last framework piece for OHM's clean /p/ohm/ cutover.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/app/main.py

@@ -112,6 +112,11 @@ async def lifespan(app: FastAPI):
         raise RuntimeError(
             f"registry mirror failed at startup ({config.registry_repo_full}/projects.yaml): {e}"
         ) from e
+    # §22.13 step 1: re-stamp the M1 bootstrap 'default' project id to the
+    # deployment's configured id (DEFAULT_PROJECT_ID) once the registry row
+    # exists, so the original corpus lands at a meaningful /p/<id>/ and
+    # 'default' is never a public URL. Idempotent no-op once done.
+    projects.restamp_default_project(config)
     if projects.default_content_repo(config) is None:
         raise RuntimeError(
             f"registry does not describe the default project "