fix pty: answer DSR (CSI 6 n) cursor-position queries

gh auth login and other cli/cli-based tools probe terminal size by
emitting \e[6n and blocking on stdin until the terminal replies with
\e[<row>;<col>R. vt10x doesn't surface DSR responses, so the child
hung forever. Scan the child's output for CSI 5 n / CSI 6 n and write
the reply back to the PTY, with carry across read boundaries.

Bump dev version to 0.1.1-dev.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

add goreleaser + GitHub Actions release pipeline

Tag-driven multi-arch release (linux/darwin × amd64/arm64) producing
GitHub Releases artifacts and a Homebrew formula pushed to a tap repo.
Also wires a basic CI workflow for build + test on PRs.

Version is now injected via -ldflags at build time, so 'noni version'
reflects the release tag.