Implement project detection and stale project analysis

[SH20RAJ]

🎯 Goal

Automatically detect project types and identify stale vs. active projects.

🚀 Features

🔍 Detected Projects:
├─ ~/Projects/my-web-app (Next.js)
│  ├─ node_modules: 450MB (last build: 2 hours ago) [KEEP]
│  └─ .next: 180MB (stale build from 3 days ago) [CLEAN]
│
├─ ~/Projects/old-project (React)
│  ├─ node_modules: 380MB (last modified: 45 days ago) [CLEAN]
│  └─ build: 25MB (created 45 days ago) [CLEAN]

🔧 Detection Logic

• Detect Next.js (package.json + .next)
• Detect React (package.json + react dependency)
• Detect Vue (package.json + vue dependency)
• Detect Xcode projects (.xcodeproj)
• Detect Flutter (pubspec.yaml)
• Detect Rust (Cargo.toml)
• Detect Go (go.mod)

📊 Staleness Criteria

• Last modified date
• Last build time
• Last git commit
• File access patterns

✅ Acceptance Criteria

• Major frameworks are detected
• Stale vs active is accurate
• Recommendations are helpful
• False positives are minimized

🔗 Related

Part of Phase 4