fix: improve TypeScript types for better IDE code hinting

- Install @types/bun and @types/jsdom for proper type definitions
- Fix mock function typing in test files
- Create jest-dom.d.ts to properly extend Bun's Matchers interface
- Remove MockedFunction imports (not supported in Bun's types)
- Cast global.fetch and useSession mocks to any where needed
- Fix mock.module return types to match expected signatures

This resolves TypeScript errors that were preventing proper code
completion and type checking in IDEs.

src/__tests__/Navigation.test.tsx

@@ -18,7 +18,7 @@ mock.module('next/link', () => ({
 
 // Mock the SessionProvider
 mock.module('@/components/SessionProvider', () => ({
-  useSession: mock(() => {}),
+  useSession: mock(() => ({ session: null, loading: false, refreshSession: mock(() => {}) })),
 }))
 
 // Mock the auth-client
@@ -29,9 +29,10 @@ mock.module('@/lib/auth-client', () => ({
 }))
 
 // Mock fetch for role API call
-global.fetch = mock(() => {})
+global.fetch = mock(async () => new Response()) as any
 
-import { useSession } from '@/components/SessionProvider'
+import { useSession as useSessionOriginal } from '@/components/SessionProvider'
+const useSession = useSessionOriginal as any
 
 describe('Epic 1: Navigation Component', () => {
   beforeEach(() => {
@@ -131,7 +132,7 @@ describe('Epic 1: Navigation Component', () => {
     });
 
     // Mock fetch to return club_admin role
-    (global.fetch).mockImplementation(async (url) => {
+    (global.fetch as any).mockImplementation(async (url: any) => {
       if (url?.toString().includes('/api/users/admin-123/role')) {
         return new Response(JSON.stringify({ role: 'club_admin' }), {
           status: 200,
@@ -165,7 +166,7 @@ describe('Epic 1: Navigation Component', () => {
     });
 
     // Mock fetch to return player role (already set in beforeEach, but explicit here)
-    (global.fetch).mockImplementation(async (url) => {
+    (global.fetch as any).mockImplementation(async (url: any) => {
       if (url?.toString().includes('/api/users/')) {
         return {
           json: () => Promise.resolve({ role: 'player' }),