Add line counter to progress log and CI badge to README

Add GitHub Actions CI workflow

Add periodic progress logging every 30s during active requests

Add comprehensive unit tests (106 tests)

Add lifecycle summary line to subprocess logs

refactor: use [req=...][pid=...] bracket format for log lines

Improve logging: structured fields, request_id correlation, compact format

Add acknowledgement for claude-max-api-proxy inspiration

Add README with usage docs, API reference, and client examples

Initial commit: Rust implementation of claude-max-api-proxy