Refactor localization system and migrate to Fyne's built-in support

Replaced the `i18n` and `toml` dependencies with Fyne's built-in language system for localization management. Updated the `Localizer` implementation to handle translations using JSON files and embed functionality. Simplified language selection and persisted settings via Fyne's preferences API.

localizer/repository.go

@@ -1,26 +0,0 @@
-package localizer
-
-import (
-	"git.kor-elf.net/kor-elf/gui-for-ffmpeg/setting"
-)
-
-type RepositoryContract interface {
-	GetCode() string
-	Save(code string) setting.Setting
-}
-
-type Repository struct {
-	settingRepository setting.RepositoryContract
-}
-
-func NewRepository(settingRepository setting.RepositoryContract) *Repository {
-	return &Repository{settingRepository: settingRepository}
-}
-
-func (r Repository) GetCode() string {
-	return r.settingRepository.GetValue("language")
-}
-
-func (r Repository) Save(code string) setting.Setting {
-	return r.settingRepository.CreateOrUpdate("language", code)
-}

localizer/view.go

@@ -4,7 +4,6 @@ import (
 	"fyne.io/fyne/v2"
 	"fyne.io/fyne/v2/widget"
 	"git.kor-elf.net/kor-elf/gui-for-ffmpeg/kernel"
-	"github.com/nicksnyder/go-i18n/v2/i18n"
 )
 
 type ViewContract interface {
@@ -35,13 +34,11 @@ func (v View) LanguageSelection(funcSelected func(lang kernel.Lang)) {
 			block.SetText(languages[i].Title)
 		})
 	listView.OnSelected = func(id widget.ListItemID) {
-		_ = v.app.GetLocalizerService().SetCurrentLanguage(languages[id])
+		_ = v.app.GetLocalizerService().SetCurrentLanguage(languages[id], true)
 		funcSelected(languages[id])
 	}
 
-	messageHead := v.app.GetLocalizerService().GetMessage(&i18n.LocalizeConfig{
-		MessageID: "languageSelectionHead",
-	})
+	messageHead := v.app.GetLocalizerService().GetMessage("languageSelectionHead")
 	v.app.GetWindow().SetContent(widget.NewCard(messageHead, "", listView))
 }
 
@@ -58,17 +55,15 @@ func LanguageSelectionForm(localizerService kernel.LocalizerContract, funcSelect
 		func(i widget.ListItemID, o fyne.CanvasObject) {
 			block := o.(*widget.Label)
 			block.SetText(languages[i].Title)
-			if languages[i].Code == currentLanguage.Lang.Code {
+			if languages[i].Code == currentLanguage.Code {
 				block.TextStyle = fyne.TextStyle{Bold: true}
 			}
 		})
 	listView.OnSelected = func(id widget.ListItemID) {
-		_ = localizerService.SetCurrentLanguage(languages[id])
+		_ = localizerService.SetCurrentLanguage(languages[id], true)
 		funcSelected(languages[id])
 	}
 
-	messageHead := localizerService.GetMessage(&i18n.LocalizeConfig{
-		MessageID: "languageSelectionFormHead",
-	})
+	messageHead := localizerService.GetMessage("languageSelectionFormHead")
 	return widget.NewCard(messageHead, "", listView)
 }