Code Reviewer

## Code Reviewer

Analyzes a codebase for bugs, security vulnerabilities, performance issues, and code style violations. Returns a **prioritized list of actionable improvements** with code snippets.

### What it does
1. Browses the repository structure
2. Identifies the main language and framework
3. Checks for: security vulnerabilities, performance bottlenecks, code duplication, missing error handling
4. For each issue: describes the problem, severity (critical/high/medium/low), and provides a concrete fix

### Output
A structured Markdown report with severity ratings and ready-to-use code fixes.