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>

TEST_IMPLEMENTATION_SUMMARY.md

@@ -427,41 +427,41 @@ All files              |   54.75 |    32.23 |   62.66 |   54.85 |
 
 ```bash
 # 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
 
 # Run specific test file
-npm test -- auth.test.js
+bun test -- auth.test.js
 
 # Run tests matching pattern
-npm test -- --testNamePattern="login"
+bun test -- --testNamePattern="login"
 ```
 
 ### Frontend
 
 ```bash
 # Run tests in watch mode (default)
-npm test
+bun test
 
 # Run tests with coverage
-npm run test:coverage
+bun run test:coverage
 
 # Run tests in watch mode (explicit)
-npm run test:watch
+bun run test:watch
 
 # Run specific test file
-npm test -- Login.test.js
+bun test -- Login.test.js
 
 # Run tests matching pattern
-npm test -- --testNamePattern="should render"
+bun test -- --testNamePattern="should render"
 ```
 
 ---
@@ -670,7 +670,7 @@ npm test -- --testNamePattern="should render"
    - Expected impact: Increase passing tests to 140+
 
 2. **Run Frontend Coverage Report**
-   - Execute `npm run test:coverage` in frontend
+   - Execute `bun run test:coverage` in frontend
    - Establish baseline coverage metrics
    - Identify coverage gaps