Forward remark field from grep results when present

The backend now sends an optional remark field on grep matches
(e.g. when lineText was truncated or when a match is multiline).
Forward it to the LLM only when non-null.

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

Author: rodion-m

src/utils/response_transformer.py

@@ -62,19 +62,26 @@ def transform_grep_response(grep_results: Dict[str, Any]) -> Dict[str, Any]:
             item["matchCount"] = result["matchCount"]
         if result.get("matches"):
             item["matches"] = [
-                {
-                    "lineNumber": match.get("lineNumber"),
-                    "startColumn": match.get("startColumn"),
-                    "endColumn": match.get("endColumn"),
-                    "lineText": match.get("lineText"),
-                }
-                for match in result["matches"]
+                _build_match_dict(match) for match in result["matches"]
             ]
         formatted_results.append(item)
 
     return {"results": formatted_results, "hint": _GREP_HINT}
 
 
+def _build_match_dict(match: Dict) -> Dict[str, Any]:
+    """Build a match dict, forwarding remark only when present."""
+    entry: Dict[str, Any] = {
+        "lineNumber": match.get("lineNumber"),
+        "startColumn": match.get("startColumn"),
+        "endColumn": match.get("endColumn"),
+        "lineText": match.get("lineText"),
+    }
+    if match.get("remark") is not None:
+        entry["remark"] = match["remark"]
+    return entry
+
+
 # Backward-compatible aliases (deprecated)
 transform_search_response_to_json = transform_search_response
 transform_grep_response_to_json = transform_grep_response