fix: use initialized tool error counter

Use the initialized tool execution error counter in the StrategicHealer path.

agents/unified_loop.py

@@ -1687,10 +1687,10 @@ class UnifiedAgentLoop(DirectToolsMixin, PromptBuilderMixin, LLMSelectionMixin,
                     _logger.info("GAP-NEW-2: TDD fail iniettato in exec_warn (%d chars)", len(self._tdd_fail_inject))
                     self._tdd_fail_inject = None
                 # GAP-4: StrategicHealer — analisi LLM pattern di fallimento (integra GAP-SELFHEAL v2)
-                if exec_errors and getattr(self, '_strategic_healer', None):
+                if _tool_exec_errors and getattr(self, '_strategic_healer', None):
                     try:
                         _sh_ctx_str = "\n".join(str(w) for w in exec_warn[-10:] if isinstance(w, str))
-                        _sh_decision = await self._strategic_healer.analyze_and_decide(exec_errors, _sh_ctx_str)
+                        _sh_decision = await self._strategic_healer.analyze_and_decide(_tool_exec_errors, _sh_ctx_str)
                         if _sh_decision and getattr(_sh_decision, 'strategy_prompt', None):
                             exec_warn.insert(0, _sh_decision.strategy_prompt)
                             _logger.info("GAP-4: StrategicHealer strategy iniettata in exec_warn")