fix: resolve all 14 ESLint warnings across the codebase

- Add varsIgnorePattern to no-unused-vars for destructuring patterns
- Fix all react-hooks/exhaustive-deps by adding missing dependencies
- Refactor useAnimatedNumber to use ref instead of stale state closure
- Wrap handleLinkResult in useCallback for stable deps
- Extract OAuth utilities from OAuthCallback.tsx to utils/oauth.ts
- Extract background config utilities to utils/backgroundConfig.ts
- Remove unused catch parameter in GiftSubscription

src/pages/Connection.tsx

@@ -43,7 +43,7 @@ export default function Connection() {
         hideLink: appConfig?.hideLink ?? false,
       },
     });
-  }, [navigate, appConfig?.subscriptionUrl, appConfig?.hideLink]);
+  }, [navigate, appConfig?.subscriptionUrl, appConfig?.hideLink, isTelegramWebApp]);
 
   useEffect(() => {
     const handleKeyDown = (e: KeyboardEvent) => {