fix: close StrategicHealer fallback result

Keep fallback fail-closed when StrategicHealer stops execution.

agents/unified_loop.py

@@ -1696,7 +1696,7 @@ class UnifiedAgentLoop(DirectToolsMixin, PromptBuilderMixin, LLMSelectionMixin,
                             _logger.info("GAP-4: StrategicHealer strategy iniettata in exec_warn")
                         if _sh_decision and getattr(_sh_decision, 'should_stop', False):
                             _logger.info("GAP-4: StrategicHealer → should_stop, interruzione fallback")
-                            return  # _run_fallback: should_stop → esci dal fallback (non c'è loop da rompere)
+                            return {"success": False, "output": "", "error": "StrategicHealer ha interrotto il fallback dopo errori di esecuzione"}
                     except Exception as _sh_loop_err:
                         _logger.debug("GAP-4: StrategicHealer loop silenced — %s", _sh_loop_err)
                 # GAP-SELFHEAL v2: dual-mode fingerprinting — raw + error-class extraction.