feat(ui): 开机自启动 + 窗口大小记忆

- win32/autostart: SetAutoStart/IsAutoStartEnabled 操作 HKCU Run 键
- win32/window_size: GetWindowSize 通过 GetWindowRect 获取窗口尺寸
- config: 新增 AutoStart、WindowWidth、WindowHeight 字段
- store: Preferences/SetPreferences 扩展支持 autoStart + windowSize
- dialog_preferences: 新增"开机自启动"复选框
- app.go: 启动时恢复窗口大小，关闭时通过 SetWindowSize 保存
- i18n: label_auto_start / hint_auto_start 三语翻译

internal/ui/dialog_preferences.go

@@ -13,7 +13,7 @@ import (
 )
 
 // preferencesDialog edits the persistent UI prefs: UI language, theme,
-// auto-lock timeout, and minimize-to-tray behaviour.
+// auto-lock timeout, minimize-to-tray, and auto-start behaviour.
 type preferencesDialog struct {
 	lang  string
 	theme themeMode
@@ -38,6 +38,10 @@ type preferencesDialog struct {
 	// system tray instead of exiting. Tray icon stays visible either way.
 	minToTray widget.Bool
 
+	// Auto-start: when on, the app is registered in the Windows Run key
+	// to launch at logon.
+	autoStart widget.Bool
+
 	okBt     widget.Clickable
 	cancelBt widget.Clickable
 }
@@ -50,6 +54,7 @@ type preferencesResult struct {
 	theme           themeMode
 	autoLockMinutes int
 	minimizeToTray  bool
+	autoStart       bool
 }
 
 // supportedLanguages is the closed set the prefs dialog exposes. Keep
@@ -63,7 +68,7 @@ var supportedLanguages = []struct {
 	{"de", "Deutsch"},
 }
 
-func newPreferencesDialog(currentLang string, currentTheme themeMode, currentAutoLock int, currentMinToTray bool) *preferencesDialog {
+func newPreferencesDialog(currentLang string, currentTheme themeMode, currentAutoLock int, currentMinToTray, currentAutoStart bool) *preferencesDialog {
 	if currentLang == "" {
 		currentLang = "en"
 	}
@@ -74,6 +79,7 @@ func newPreferencesDialog(currentLang string, currentTheme themeMode, currentAut
 	d.autoLockEd.SingleLine = true
 	d.autoLockEd.SetText(strconv.Itoa(currentAutoLock))
 	d.minToTray.Value = currentMinToTray
+	d.autoStart.Value = currentAutoStart
 	return d
 }
 
@@ -98,6 +104,7 @@ func (d *preferencesDialog) Layout(
 			theme:           d.theme,
 			autoLockMinutes: mins,
 			minimizeToTray:  d.minToTray.Value,
+			autoStart:       d.autoStart.Value,
 		})
 		return layout.Dimensions{Size: gtx.Constraints.Max}
 	}
@@ -164,6 +171,10 @@ func (d *preferencesDialog) Layout(
 			layout.Rigid(material.CheckBox(th, &d.minToTray, i18n.T("label_minimize_to_tray")).Layout),
 			layout.Rigid(layout.Spacer{Height: unit.Dp(2)}.Layout),
 			layout.Rigid(material.Caption(th, i18n.T("hint_minimize_to_tray")).Layout),
+			layout.Rigid(layout.Spacer{Height: unit.Dp(12)}.Layout),
+			layout.Rigid(material.CheckBox(th, &d.autoStart, i18n.T("label_auto_start")).Layout),
+			layout.Rigid(layout.Spacer{Height: unit.Dp(2)}.Layout),
+			layout.Rigid(material.Caption(th, i18n.T("hint_auto_start")).Layout),
 		)
 	}