feat: mcp and backfill fixes

backend/src/utils/read/models.py

@@ -77,6 +77,7 @@ class MediaRef(BaseModel):
     mime: str | None = None
     file_size: int | None = None
     ttl_seconds: int | None = None
+    extracted_text: str | None = None
 
 
 class ReactionCount(BaseModel):