v0.1.3

feat: add family-group subcommand to group patents by patent family

- New `gp-cli family-group` command: given a list of patent numbers,
  fetches family_applications for each and groups them by patent family
- Skip optimization: once a family member is identified from a fetch,
  the remaining members are skipped — minimising total API calls
- Supports --format json/text/tsv, --input-file, --output-dir,
  --delay, --no-header, --quiet, --minify flags
- Applies 1000–1500 ms random jitter between requests (bulk mode)
  to avoid bot detection; --delay overrides
- Integration tests: 9 cases covering grouping, fetch-count
  optimization, all output formats, --input-file, --output-dir
- Bump version to 0.1.3

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>