feat: comprehensive oxlint cleanup - remove unused code

🧹 Cleanup Summary:
- Fixed 83 oxlint warnings across 50+ files
- Removed unused imports, variables, and functions
- Maintained all functional code and error handling
- Improved bundle size and code maintainability

📝 Key Changes:
- Cleaned unused React hooks (useState, useEffect, useClashInfo)
- Removed unused Material-UI imports (useTheme, styled components)
- Deleted unused interfaces and type definitions
- Fixed spread operator usage and boolean casting
- Simplified catch parameters where appropriate

🎯 Files Modified:
- React components: home.tsx, settings, profiles, etc.
- Custom hooks: use-*.ts files
- Utility functions and type definitions
- Configuration files

✅ Result: 0 oxlint warnings (from 83 warnings)
🔧 All functionality preserved
📦 Reduced bundle size through dead code elimination

src/components/setting/mods/tun-viewer.tsx

@@ -70,7 +70,7 @@ export const TunViewer = forwardRef<DialogRef>((props, ref) => {
       await patchClash({ tun });
       await mutateClash(
         (old) => ({
-          ...(old! || {}),
+          ...old!,
           tun,
         }),
         false,
@@ -118,7 +118,7 @@ export const TunViewer = forwardRef<DialogRef>((props, ref) => {
               await patchClash({ tun });
               await mutateClash(
                 (old) => ({
-                  ...(old! || {}),
+                  ...old!,
                   tun,
                 }),
                 false,