feat: implement ToolStartToGoal and fix LLM service initialization

- Add ToolStartToGoal implementation with AI-driven goal automation
- Fix LLM service not initialized issue by applying global AI config to XTDriver creation
- Ensure XTDriver is created with proper AI services from the first initialization
- Add StartToGoal method to StepMobile for goal-oriented automation
- Register ToolStartToGoal in MCP server and add corresponding action type
- Add comprehensive test case for StartToGoal functionality
- Fix ReturnSchema consistency across AI tools (StartToGoal, AIAction, Finished)
- Extract AI service options in MCP argument processing

This resolves the root cause where XTDriver was created without AI services
in runStepMobileUI, ensuring only one XTDriver initialization with complete
AI service configuration.

uixt/option/action.go

@@ -73,7 +73,6 @@ const (
 	ACTION_KeyCode                  ActionName = "keycode"
 	ACTION_Delete                   ActionName = "delete"    // delete action
 	ACTION_Backspace                ActionName = "backspace" // backspace action
-	ACTION_AIAction                 ActionName = "ai_action" // action with ai
 	ACTION_TapBySelector            ActionName = "tap_by_selector"
 	ACTION_HoverBySelector          ActionName = "hover_by_selector"
 	ACTION_Hover                    ActionName = "hover"       // generic hover action
@@ -101,9 +100,13 @@ const (
 	ACTION_InstallApp      ActionName = "install_app"
 	ACTION_UninstallApp    ActionName = "uninstall_app"
 	ACTION_DownloadApp     ActionName = "download_app"
-	ACTION_Finished        ActionName = "finished"
 	ACTION_CallFunction    ActionName = "call_function"
 
+	// AI actions
+	ACTION_StartToGoal ActionName = "start_to_goal" // start to goal action
+	ACTION_AIAction    ActionName = "ai_action"     // action with ai
+	ACTION_Finished    ActionName = "finished"      // finished action
+
 	// anti-risk actions
 	ACTION_SetTouchInfo     ActionName = "set_touch_info"
 	ACTION_SetTouchInfoList ActionName = "set_touch_info_list"
@@ -178,8 +181,10 @@ type ActionOptions struct {
 	Params []float64 `json:"params,omitempty" yaml:"params,omitempty" desc:"Generic parameter array"`
 
 	// AI related
-	Prompt  string `json:"prompt,omitempty" yaml:"prompt,omitempty" desc:"AI action prompt"`
-	Content string `json:"content,omitempty" yaml:"content,omitempty" desc:"Content for finished action"`
+	Prompt     string `json:"prompt,omitempty" yaml:"prompt,omitempty" desc:"AI action prompt"`
+	Content    string `json:"content,omitempty" yaml:"content,omitempty" desc:"Content for finished action"`
+	LLMService string `json:"llm_service,omitempty" yaml:"llm_service,omitempty" desc:"LLM service type for AI actions"`
+	CVService  string `json:"cv_service,omitempty" yaml:"cv_service,omitempty" desc:"Computer vision service type for AI actions"`
 
 	// Time related
 	Seconds      float64 `json:"seconds,omitempty" yaml:"seconds,omitempty" desc:"Sleep duration in seconds"`
@@ -679,6 +684,9 @@ func (o *ActionOptions) validateActionSpecificFields(actionType ActionName) erro
 		ACTION_AIAction: func() error {
 			return o.requireFields("prompt", o.Prompt != "")
 		},
+		ACTION_StartToGoal: func() error {
+			return o.requireFields("prompt", o.Prompt != "")
+		},
 		ACTION_Finished: func() error {
 			return o.requireFields("content", o.Content != "")
 		},
@@ -750,7 +758,8 @@ func (o *ActionOptions) GetMCPOptions(actionType ActionName) []mcp.ToolOption {
 		ACTION_Sleep:                    {"seconds"},
 		ACTION_SleepMS:                  {"platform", "serial", "milliseconds"},
 		ACTION_SleepRandom:              {"platform", "serial", "params"},
-		ACTION_AIAction:                 {"platform", "serial", "prompt"},
+		ACTION_AIAction:                 {"platform", "serial", "prompt", "llm_service", "cv_service"},
+		ACTION_StartToGoal:              {"platform", "serial", "prompt", "llm_service", "cv_service"},
 		ACTION_Finished:                 {"content"},
 		ACTION_ListAvailableDevices:     {},
 		ACTION_SelectDevice:             {"platform", "serial"},