Added "Add Game" button function (#33)

* All games will be linked

* feat: Add 'Add Game' button to Settings tab

- Added 'Add Game' button to Games to Watch section in Settings
- Implemented logic to add custom games via search input
- Fixed alignment issue with games filter search bar
- Added English translations for new UI elements

* fix PR 33 review issues

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Co-authored-by: ethanblazkowicz <wow990922@outlook.com>
Co-authored-by: LeonSparta <46887992+LeonSparta@users.noreply.github.com>
Co-authored-by: Fengqing Liu <fq_aaron@hotmail.com>

src/i18n/translator.py

@@ -177,6 +177,8 @@ class GUISettings(TypedDict):
     games_to_watch: str
     games_help: str
     search_games: str
+    add_game: str
+    add_game_hint: str
     select_all: str
     deselect_all: str
     selected_games: str