feat: implement UI automation test history isolation

- Add ResetHistory option to PlanningOptions and ActionOptions
- Implement task completion detection with isTaskFinished() method
- Add executeActions() method to separate action execution logic
- Modify ConversationHistory.Clear() to completely clear all messages including system message
- Refactor StartToGoal() to automatically reset history on first attempt
- Add WithResetHistory() option function for consistent API
- Consolidate test files into driver_ext_ai_test.go with comprehensive test coverage

uixt/ai/planner.go

@@ -23,6 +23,7 @@ type PlanningOptions struct {
 	UserInstruction string          `json:"user_instruction"` // append to system prompt
 	Message         *schema.Message `json:"message"`
 	Size            types.Size      `json:"size"`
+	ResetHistory    bool            `json:"reset_history"` // whether to reset conversation history before planning
 }
 
 // PlanningResult represents the result of planning
@@ -85,6 +86,12 @@ func (p *Planner) Call(ctx context.Context, opts *PlanningOptions) (*PlanningRes
 		return nil, errors.Wrap(err, "validate planning parameters failed")
 	}
 
+	// reset conversation history if requested
+	if opts.ResetHistory {
+		p.history.Clear() // Clear everything including system message for complete isolation
+		log.Info().Msg("conversation history reset for planner")
+	}
+
 	// prepare prompt
 	if len(p.history) == 0 && opts.UserInstruction != "" {
 		// add system message