Add Pi Research Agent package

Autonomous research agent with web search, source analysis, and report synthesis.
Built on Pi agent core. Available as CLI, programmatic API, and MCP server.

Features:
- 4 built-in tools: web_search, read_url, save_note, synthesize_report
- CLI with TUI and print modes
- Programmatic API via ResearchAgent class
- MCP server with 3 tools: research, quick_search, read_url
- Skills system for custom research behavior
- Automatic .env file loading for API keys
- Configurable max turns, output formats (markdown/JSON/bullet)
- Automatic report saving to research-output/

.gitignore

@@ -39,3 +39,4 @@ plans/
 .pi/hf-sessions/
 .pi/hf-sessions-backup/
 collect.sh
+research-output/