fix(tui): keep memory tool previews one-line

Avoid malformed multi-line memory tool labels when the model omits a target by keeping the add preview compact and quote-adjacent.

agent/display.py

@@ -223,7 +223,8 @@ def build_tool_preview(tool_name: str, args: dict, max_len: int | None = None) -
         target = args.get("target", "")
         if action == "add":
             content = _oneline(args.get("content", ""))
-            return f"+{target}: \"{content[:25]}{'...' if len(content) > 25 else ''}\""
+            target_prefix = f"+{target}: " if target else "+"
+            return f"{target_prefix}\"{content[:25]}{'...' if len(content) > 25 else ''}\""
         elif action == "replace":
             old = _oneline(args.get("old_text") or "") or "<missing old_text>"
             return f"~{target}: \"{old[:20]}\""

tests/agent/test_display.py

@@ -82,6 +82,11 @@ class TestBuildToolPreview:
         result = build_tool_preview("memory", {"action": "add", "target": "user", "content": "test note"})
         assert result is not None
         assert "user" in result
+        assert "\n" not in result
+
+    def test_memory_tool_add_without_target_stays_one_line(self):
+        result = build_tool_preview("memory", {"action": "add", "content": "User identifies as a cutie patootie."})
+        assert result == '+"User identifies as a cuti..."'
 
     def test_memory_replace_missing_old_text_marked(self):
         # Avoid empty quotes "" in the preview when old_text is missing/None.