Fix unused variables and clean up codebase

- Remove unused NextResponse imports from API routes
- Remove unused result variable in teams DELETE route
- Remove unused Link import from page.tsx
- Remove unused inspectTextSourceProperties function from obsClient.js
- Fix unused catch variables and response variables in test files
- Clean up all ESLint warnings for unused variables

app/api/__tests__/streams.test.ts

@@ -27,8 +27,6 @@ describe('/api/streams', () => {
       
       mockDb.all.mockResolvedValue(mockStreams);
       
-      const _response = await GET();
-      
       expect(mockDb.all).toHaveBeenCalledWith(
         expect.stringContaining('SELECT * FROM')
       );
@@ -40,8 +38,6 @@ describe('/api/streams', () => {
     it('returns empty array when no streams exist', async () => {
       mockDb.all.mockResolvedValue([]);
       
-      const _response = await GET();
-      
       const { NextResponse } = require('next/server');
       expect(NextResponse.json).toHaveBeenCalledWith([]);
     });
@@ -50,8 +46,6 @@ describe('/api/streams', () => {
       const dbError = new Error('Database connection failed');
       mockDb.all.mockRejectedValue(dbError);
       
-      const _response = await GET();
-      
       const { NextResponse } = require('next/server');
       expect(NextResponse.json).toHaveBeenCalledWith(
         { error: 'Failed to fetch streams' },
@@ -64,8 +58,6 @@ describe('/api/streams', () => {
       const { getDatabase } = require('@/lib/database');
       getDatabase.mockRejectedValue(connectionError);
       
-      const _response = await GET();
-      
       const { NextResponse } = require('next/server');
       expect(NextResponse.json).toHaveBeenCalledWith(
         { error: 'Failed to fetch streams' },