Add CODEOWNERS requiring @NimbleBrainInc/core approval

Bump version to 0.3.0

Add skill://folk/usage resource for LLM tool routing guidance

Upgrade to MCPB 0.4 manifest with MTF L2 compliance

docs: add MIT license file and README badges

style: fix ruff format for server.py

feat: add Folk ID validation to all ID-accepting tools

feat: add group filtering and custom field support

fix: use valid iCalendar RRULE format for reminders

fix: improve tool descriptions to require find_person first

Fix reminder recurrenceRule format and add tests

Fix reminder DTSTART format to use UTC with Z suffix

Fix reminder API to use iCalendar recurrenceRule format

Redesign MCP tools for efficiency and fix Folk API request formats

Add make pack command for local bundle testing