fix(precedents): separate court rulings from committee decisions correctly

- DB: add 'all_committees' virtual source_kind covering internal_committee
  + external_upload appeals_committee rows in one query
- DB: stats now count all case_law rows (not just external_upload),
  fixing the precedents_total that excluded 44 internal-committee records
- UI: courts table filters to source_type=court_ruling only;
  committees table uses the new all_committees query

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web-ui/src/components/precedents/library-list-panel.tsx

@@ -313,8 +313,8 @@ export function LibraryListPanel() {
     limit: 200,
   };
 
-  const courts = usePrecedents({ ...sharedFilters, sourceKind: "external_upload" });
-  const committee = usePrecedents({ ...sharedFilters, sourceKind: "internal_committee" });
+  const courts = usePrecedents({ ...sharedFilters, sourceKind: "external_upload", sourceType: "court_ruling" });
+  const committee = usePrecedents({ ...sharedFilters, sourceKind: "all_committees" });
 
   return (
     <div className="space-y-8">