fix: improve error handling and type safety

- Replaced 'any' types with proper TypeScript types
- Improved error handling with instanceof checks
- Removed unused imports (calculateExpectedTeamScore)
- Updated error messages to be more descriptive
- Removed deprecated eslint.config.mjs file

src/app/api/users/[id]/role/route.ts

@@ -39,7 +39,7 @@ export async function GET(
     }
 
     return NextResponse.json({ role: user.role });
-  } catch (error) {
+  } catch {
     return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
   }
 }