fix(classification): harden registration updates

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a02b22-9638-76d2-bbff-b7ea1770b118

api/routers/repos.py

@@ -604,10 +604,27 @@ async def update_repo_with_classification(
     """Patch repo metadata including classification spine fields."""
     repo = await _get_repo_by_slug(slug, session)
     payload = body.model_dump(exclude_unset=True)
-    domain_result = await session.execute(select(Domain).where(Domain.id == repo.domain_id))
-    domain_obj = domain_result.scalar_one_or_none()
+    requested_domain_slug = payload.pop("domain_slug", None)
+    if requested_domain_slug is not None:
+        domain_result = await session.execute(
+            select(Domain).where(Domain.slug == requested_domain_slug)
+        )
+        domain_obj = domain_result.scalar_one_or_none()
+        if domain_obj is None:
+            raise HTTPException(
+                status_code=404,
+                detail=f"Domain '{requested_domain_slug}' not found",
+            )
+    else:
+        domain_result = await session.execute(
+            select(Domain).where(Domain.id == repo.domain_id)
+        )
+        domain_obj = domain_result.scalar_one_or_none()
     domain_slug = domain_obj.slug if domain_obj else ""
-    if classification_fields_set(payload):
+    classification_requested = classification_fields_set(payload)
+    if classification_requested or (
+        requested_domain_slug is not None and repo.category is not None
+    ):
         merged = {
             "category": payload.get("category", repo.category),
             "secondary_domains": payload.get("secondary_domains", repo.secondary_domains),
@@ -620,6 +637,8 @@ async def update_repo_with_classification(
             fields=merged,
             require_complete=True,
         )
+    if requested_domain_slug is not None:
+        repo.domain_id = domain_obj.id
     for field, value in payload.items():
         setattr(repo, field, value)
     await session.commit()

api/schemas/managed_repo.py

@@ -80,6 +80,7 @@ class RepoCreate(CoreRepoCreate, ClassificationFields):
 
 
 class RepoUpdate(ClassificationFields):
+    domain_slug: str | None = None
     name: str | None = None
     local_path: str | None = None
     remote_url: str | None = None
@@ -176,4 +177,4 @@ class RepoScopeHealth(BaseModel):
     local_path: str | None = None
     path_available: bool
     scope_needs_review: bool
-    scope_issue_details: list[ScopeIssueDetail]
+    scope_issue_details: list[ScopeIssueDetail]