Add FFmpeg utilities configuration UI and automated downloading

Introduce a new UI for configuring FFmpeg, FFprobe, and FFplay paths with file selection and error handling. Add platform-specific logic for downloading and extracting FFmpeg binaries directly within the application, improving user experience.

internal/controller/main.go

@@ -13,7 +13,7 @@ type ControllerContract interface {
 
 type controller struct {
 	app    application.AppContract
-	window window.MainWindowContract
+	window window.WindowContract
 }
 
 func NewController(app application.AppContract) ControllerContract {
@@ -26,11 +26,10 @@ func NewController(app application.AppContract) ControllerContract {
 }
 
 func (c *controller) Start() {
-	c.window.Show()
-
 	isDefault, err := c.initLanguage()
 	if err != nil {
 		c.startWithError(err)
+		c.window.Show()
 		return
 	}
 
@@ -46,14 +45,21 @@ func (c *controller) Start() {
 			c.verificareaFFmpeg()
 		})
 		c.window.SetContent(content)
+		c.window.Show()
 		return
 	}
 
 	c.window.InitLayout()
 	c.verificareaFFmpeg()
+	c.window.Show()
 }
 
 func (c *controller) verificareaFFmpeg() {
+	if !c.app.GetFFmpegService().UtilityCheck() {
+		c.settingConvertor(false)
+		return
+	}
+
 	c.convertor()
 }