i18n(ru/zh-Hans/zh-Hant/hu/fa): translate TUN settings, unify MTU, use resx (#7787)

* feat(i18n,ui): externalize TUN settings labels, add translations

- Replace hard-coded labels "Auto Route", "Strict Route", "Stack",
  and "Mtu/mtu" with resource keys in both Avalonia and WPF views:
  - v2rayN/v2rayN.Desktop/Views/AddServerWindow.axaml
  - v2rayN/v2rayN.Desktop/Views/OptionSettingWindow.axaml
  - v2rayN/v2rayN/Views/AddServerWindow.xaml
  - v2rayN/v2rayN/Views/OptionSettingWindow.xaml
- Add new resource keys in ResUI:
  TbSettingsTunAutoRoute, TbSettingsTunStrictRoute,
  TbSettingsTunStack, TbSettingsTunMtu (unified casing as "MTU").
  Files:
  - v2rayN/ServiceLib/Resx/ResUI.resx
- Provide translations in:
  - v2rayN/ServiceLib/Resx/ResUI.ru.resx
  - v2rayN/ServiceLib/Resx/ResUI.zh-Hans.resx
  - v2rayN/ServiceLib/Resx/ResUI.zh-Hant.resx
  - v2rayN/ServiceLib/Resx/ResUI.fa-Ir.resx
  - v2rayN/ServiceLib/Resx/ResUI.hu.resx
- Normalize XML comments/whitespace in .resx files.
- Update submodule v2rayN/GlobalHotKeys to 5201dd5.

No breaking changes.

* i18n: TUN labels across locales; unify MTU

* chore: ignore local IDE/venv files

* chore(resx): regenerate ResUI.Designer with TUN string accessors

- Add strongly-typed accessors in ServiceLib.Resx.ResUI:
  - TbSettingsTunAutoRoute → "Auto Route"
  - TbSettingsTunStrictRoute → "Strict Route"
  - TbSettingsTunStack → "Stack"
  - TbSettingsTunMtu → "MTU"
- Keep auto-generated structure intact; normalize minor whitespace.

Refs: v2rayN/ServiceLib/Resx/ResUI.resx
No functional changes beyond exposing new i18n keys.

* chore(gitignore): ignore JetBrains Rider artifacts (.idea/, *.sln.iml)

---------

Co-authored-by: Aleksandr Miheichev <alexandr.gmail@tuta.com>

.gitignore

@@ -397,4 +397,5 @@ FodyWeavers.xsd
 *.msp
 
 # JetBrains Rider
-*.sln.iml
+.idea/
+*.sln.iml