[codex] Add IDE session tracking

[defidevrel]

Summary

Adds manual IDE session tracking for GUI-first tools like Cursor.

• adds vibe ide start [tool], vibe ide stop [tool], and vibe ide status
• stores IDE session project metadata so stop/status can calculate commits, lines, files, duration, and momentum using the existing git scoring model
• refreshes active IDE sessions before status, log, and share so stats show up alongside wrapped CLI sessions
• documents the Cursor flow and adds IDE/Cursor package keywords

Impact

Users can now track Cursor or another IDE without needing a shell wrapper around a long-running CLI process. Completed IDE sessions are normal Vibetime sessions, so they appear in local stats, share cards, and the opt-in leaderboard.

Validation

• npm run build
• smoke-tested vibe ide start cursor, vibe ide status, and vibe ide stop cursor in a temporary HOME and temporary git repo