Manual merge of story 399 feature branch, adapted for the current CLI
parser (which includes the init subcommand from 429).
- storkit --port 3000 sets the listening port
- storkit --port=3000 also works
- Port resolution: CLI flag > STORKIT_PORT env > default 3001
- Supports combining with init: storkit init --port 3000 /path
- Replaces CliDirective enum with CliArgs struct that handles both
--port and init in a single pass
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>