feat: add shared claude binary detection module

Introduces a dedicated module for detecting Claude Code binary installations
with support for multiple sources including NVM, aliased paths, and
version-based selection. This shared module improves the reliability of
finding Claude installations across different environments.

Key features:
- Supports multiple installation sources (NVM, system, homebrew, npm, yarn, bun)
- Handles aliased paths from 'which' command
- Version-aware selection to prefer latest installations
- Database caching of discovered binary paths
- Comprehensive logging for debugging
- Environment variable preservation for NVM compatibility

The implementation is inspired by:
- https://github.com/getAsterisk/claudia/pull/3
- https://github.com/getAsterisk/claudia/pull/4

src-tauri/src/lib.rs

@@ -5,6 +5,7 @@ pub mod commands;
 pub mod sandbox;
 pub mod checkpoint;
 pub mod process;
+pub mod claude_binary;
 
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {