feat(sources): admin page to add and remove git sources (TODO.md L4)

app/api/sync.py

@@ -15,9 +15,12 @@ stale button state (§7.4 adaptation, phase locked decisions).
 Pipeline (the canonical "mirror the repos" action — phase locked
 decisions):
 
-1. resolve the ``BOR_GIT_SOURCES`` URLs — empty/missing fails loudly
-   (``no git sources configured``) instead of silently importing the
-   legacy local directories;
+1. resolve the effective git sources — the ``git_sources`` DB rows,
+   else the ``BOR_GIT_SOURCES`` fallback
+   (:func:`app.rag.git_sources.effective_git_sources`, shared with the
+   CLI) — empty on both origins fails loudly (``no git sources
+   configured``) instead of silently importing the legacy local
+   directories;
 2. :func:`scripts.git_sync.clone_or_pull` each repo into
    ``BOR_SOURCES_DIR/<repo-name>/`` (phase 28 — reused, not
    re-implemented; a failing repo aborts before any import);
@@ -44,6 +47,8 @@ from fastapi import APIRouter, Depends, HTTPException
 
 from app.config import get_settings
 from app.core.auth import require_admin
+from app.db import SessionLocal
+from app.rag.git_sources import effective_git_sources
 from app.rag.importer import ImportSummary, import_sources
 from app.rag.llm import LLMClient
 from app.rag.overview import regenerate_overview
@@ -141,13 +146,23 @@ async def _run_sync() -> None:
     _status.error = None
     try:
         settings = get_settings()
-        git_urls = settings.git_source_list
+        # The background task has no request session: open a short-lived
+        # one around the shared phase-35 resolver (DB rows win, the
+        # BOR_GIT_SOURCES list is a fallback while the table is empty).
+        db = SessionLocal()
+        try:
+            git_urls, origin = effective_git_sources(db)
+        finally:
+            db.close()
         if not git_urls:
-            # The button targets BOR_GIT_SOURCES only (manual --source
-            # dirs have no repo to clone) — an empty config fails loudly
-            # instead of silently importing the legacy directories.
-            raise GitSyncError("no git sources configured (BOR_GIT_SOURCES)")
-        logger.info("sync: started repos=%d", len(git_urls))
+            # The button targets git sources only (manual --source dirs
+            # have no repo to clone) — an empty config on *both* origins
+            # fails loudly instead of silently importing the legacy
+            # directories.
+            raise GitSyncError(
+                "no git sources configured (git_sources table empty and BOR_GIT_SOURCES unset)"
+            )
+        logger.info("sync: started repos=%d origin=%s", len(git_urls), origin)
         sources_root = Path(settings.sources_dir).expanduser()
         sources = [clone_or_pull(url, sources_root / repo_name(url)) for url in git_urls]
         llm = LLMClient()