docs: update npm commands to bun in README and documentation files

- Replace npm install with bun install
- Replace npm start/test/build with bun equivalents
- Update deployment and testing documentation
- Maintain consistency with project's bun-first approach

🤖 Generated with [AI Assistant]

Co-Authored-By: AI Assistant <noreply@ai-assistant.com>

TESTING.md

@@ -206,16 +206,16 @@ describe('Login Component', () => {
 cd backend
 
 # Run all tests
-npm test
+bun test
 
 # Run tests in watch mode
-npm run test:watch
+bun run test:watch
 
 # Run tests with coverage
-npm run test:coverage
+bun run test:coverage
 
 # Run tests with verbose output
-npm run test:verbose
+bun run test:verbose
 ```
 
 ### Frontend Tests
@@ -224,13 +224,13 @@ npm run test:verbose
 cd frontend
 
 # Run all tests (interactive watch mode)
-npm test
+bun test
 
 # Run tests with coverage
-npm run test:coverage
+bun run test:coverage
 
 # Run tests in watch mode
-npm run test:watch
+bun run test:watch
 ```
 
 ### Run All Tests
@@ -239,10 +239,10 @@ From the project root:
 
 ```bash
 # Backend
-cd backend && npm test
+cd backend && bun test
 
 # Frontend
-cd frontend && npm test
+cd frontend && bun test
 ```
 
 ## Coverage Reports
@@ -296,11 +296,11 @@ To view HTML coverage reports:
 
 ```bash
 # Backend
-cd backend && npm test -- --coverage
+cd backend && bun test -- --coverage
 open coverage/lcov-report/index.html
 
 # Frontend
-cd frontend && npm run test:coverage
+cd frontend && bun run test:coverage
 open coverage/lcov-report/index.html
 ```
 
@@ -494,12 +494,12 @@ jest.mock('react-leaflet', () => ({
 
 1. **Run specific test files**:
    ```bash
-   npm test -- auth.test.js
+   bun test -- auth.test.js
    ```
 
 2. **Run tests matching pattern**:
    ```bash
-   npm test -- --testNamePattern="login"
+   bun test -- --testNamePattern="login"
    ```
 
 3. **Skip tests during development**:
@@ -559,16 +559,16 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v2
-      - run: cd backend && npm install
-      - run: cd backend && npm test -- --coverage
+      - run: cd backend && bun install
+      - run: cd backend && bun test -- --coverage
 
   frontend-tests:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v2
-      - run: cd frontend && npm install
-      - run: cd frontend && npm run test:coverage
+      - run: cd frontend && bun install
+      - run: cd frontend && bun run test:coverage
 ```
 
 ## Resources