feat(ledger): the CSS consumer map — code_shape_consumers edges (shape → file whose markup names the class, count), migration 0086, resolve_consumers (own-file row when the template defines the class, else every other definition), sync_repo_consumers rebuilt from the archive on every refresh, consumers_of; derived, so not backed up (milestone 302 step 2, #2935)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/scribe/services/coverage.py

@@ -555,7 +555,8 @@ async def compute_coverage(
         # The binding's own ref when it names one (#2873: a dev-first project
         # has its ledger follow dev), else the forge's default branch.
         ref = binding.ref or await forge.default_branch(api_repo)
-        definitions = definitions_from_archive(await forge.archive(api_repo, ref))
+        scan = scan_archive(await forge.archive(api_repo, ref))
+        definitions = scan.definitions
         # The head commit is provenance sugar on the ledger rows; failing to
         # learn it must not fail the sync — the ref names the point well
         # enough and the row timestamps carry the when.
@@ -567,6 +568,13 @@ async def compute_coverage(
             project_id, key, definitions, seen_marker=marker
         )
         served.append((key, ref))
+        # The CSS consumer map (milestone 302) rides the same archive: which
+        # files' markup names each class. Mechanical and recomputable, so it
+        # must not be able to fail the refresh either.
+        try:
+            await shape_ledger.sync_repo_consumers(project_id, key, scan.references)
+        except Exception:
+            logger.warning("consumer map sync failed for %s", key, exc_info=True)
         # Propose while the bodies are in hand — the one moment they exist.
         # Canonical marking below only touches rows the proposer leaves
         # alone (a canon's own location never gets a proposal), so the order