fix: comment out premature db::crdt references that broke build

The 490 merge introduced references to a db::crdt module that doesn't
exist yet (it's part of story 491). Commented out with TODO(491)
markers so master compiles. The crdt_state.rs module from 490 is
intact — these are just the call sites that will be wired up when
491 lands.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/agents/lifecycle.rs

@@ -65,9 +65,8 @@ fn move_item<'a>(
         }
     }
 
-    // Write the new stage through CRDT ops (also does legacy shadow write).
-    // Fire-and-forget; a missing database (e.g. in tests) is silently ignored.
-    crate::db::crdt::crdt_write(story_id, target_dir, &target_path);
+    // TODO(491): Wire up CRDT state transitions once the watcher story lands.
+    // crate::db::crdt::crdt_write(story_id, target_dir, &target_path);
 
     slog!("[lifecycle] Moved '{story_id}' from work/{src_dir}/ to work/{target_dir}/");
     Ok(Some(src_dir))