v0.5.0 - Phase 2: Callers Tracking, Event Architecture Map & Offline Schema Extractor

• Added lg callers <Method|Class>: Deterministic call-site and reference tracker across PHP and Vue/TS/JS with caller context
• Added lg event-map [<filter>]: Laravel Event -> Listener -> Queue -> Job dependency graph mapper across modular packages
• Added lg schema <Model>: Offline database schema, columns, casts, fillables, and Eloquent relationships extractor
• Added full --json machine-readable mode across all new commands
• Added MCP server tools: localgrep_callers, localgrep_event_map, localgrep_schema
• 25 automated unit tests passing in 0.040s