fix(search): address remaining review follow-ups for #1403

- Correct warning wording: "FTS extension unavailable" → "FTS indexes
  missing" to avoid platform-capability confusion
- Update stale isHybridSearchReady comment to reference #1403 and
  ftsAvailable per-query signal
- Add TODO(#1403) at both api.ts call sites documenting that the server
  API path does not yet propagate ftsAvailable to the response

gitnexus/src/core/search/hybrid-search.ts

@@ -113,12 +113,13 @@ export const mergeWithRRF = (
 };
 
 /**
- * Check if hybrid search is available
- * LadybugDB FTS is always available once the database is initialized.
- * Semantic search is optional - hybrid works with just FTS if embeddings aren't ready.
+ * Check if hybrid search is available.
+ * FTS indexes may be missing on read-only MCP connections (see #1403);
+ * callers should inspect `ftsAvailable` from searchFTSFromLbug for
+ * per-query availability. This helper is a coarse gate only.
  */
 export const isHybridSearchReady = (): boolean => {
-  return true; // FTS is always available via LadybugDB when DB is open
+  return true; // FTS is attempted on every query; ftsAvailable signals actual availability
 };
 
 /**

gitnexus/src/mcp/local/local-backend.ts

@@ -979,7 +979,7 @@ export class LocalBackend {
       timing,
       ...(!ftsUsed && {
         warning:
-          'FTS extension unavailable - keyword search degraded. Run: gitnexus analyze --force to rebuild indexes.',
+          'FTS indexes missing — keyword search degraded. Run: gitnexus analyze --force to rebuild indexes.',
       }),
     };
   }

gitnexus/src/server/api.ts

@@ -1077,6 +1077,8 @@ export const createServer = async (port: number, host: string = '127.0.0.1') =>
             sources: ['semantic'],
           }));
         } else if (mode === 'bm25') {
+          // TODO(#1403): propagate ftsAvailable to API response so server
+          // users get the same "indexes missing" warning as MCP/CLI callers.
           searchResults = (await searchFTSFromLbug(query, limit)).results;
           searchResults = searchResults.map((r: any, i: number) => ({
             ...r,
@@ -1091,6 +1093,7 @@ export const createServer = async (port: number, host: string = '127.0.0.1') =>
               await import('../core/embeddings/embedding-pipeline.js');
             searchResults = await hybridSearch(query, limit, executeQuery, semSearch);
           } else {
+            // TODO(#1403): propagate ftsAvailable to API response (see bm25 branch above).
             searchResults = (await searchFTSFromLbug(query, limit)).results;
           }
         }