feat(typefully): add queue commands and split test suite

[frankdilo]

What changed

• Added queue command support to Typefully CLI:
  • queue:get [social_set_id] --start-date <YYYY-MM-DD> --end-date <YYYY-MM-DD>
  • queue:schedule:get [social_set_id]
  • queue:schedule:put [social_set_id] --rules '<json-array>'
• Added clear queue argument validation and default social-set behavior for the new commands.
• Documented queue commands and examples in skills/typefully/SKILL.md.
• Updated skills/typefully/CHANGELOG.md with user-facing queue command notes.
• Split the monolithic test file into command-focused suites and added targeted npm test scripts.

Validation

• npm test
• Command-specific runs:
  • npm run test:queue
  • npm run test:drafts
  • npm run test:all

Notes

• Changes are split into two commits for review:
  1. feat: add queue commands and docs updates
  2. test: split CLI tests into command-focused files