Add Cursor IDE as a new data source

[wjessup]

Summary

• Adds Cursor IDE as a new data source, parsing conversations from its local SQLite database (state.vscdb)
• Cursor-specific parsing logic lives in a new dataclaw/parsers/cursor.py module, with parser.py delegating to it
• Extracts user/assistant messages, tool calls (with full structured outputs), thinking blocks, model info, and token counts
• Handles MCP tool prefix stripping, nested JSON unwrapping, and workspace-based project grouping
• Includes 11 tests covering discovery, session parsing, tool calls, thinking, edge cases

Test plan

• All 301 tests pass (290 existing + 11 new cursor tests)
• dataclaw list --source cursor discovers projects correctly
• dataclaw export --source cursor --no-push produces valid JSONL with full tool outputs preserved
• Verified on real Cursor database: 1562 sessions, 141k messages, 69k tool uses, zero parse errors

Made with Cursor