crossby v0.2.4 — first public release

One config, every AI tool. Sync rules, agents, skills, permissions,
hooks, and MCP servers across Claude, Copilot, Gemini, Codex, Cursor,
OpenCode, VS Code, and Antigravity, and hand off live sessions between
them.

Sync

• crossby agents convert — translate subagent definitions between
  Claude, Cursor, Gemini, Copilot, and Codex.
• --strategy translate — per-file agent + skill rewrites with blocks for fields lost in translation (e.g. Claude allowed-tools, permissionMode: plan).
• --plan / --doctor / --validate-target — pre-write inspection modes.
• Persistent sync report at .crossby/sync-report.md after every real
  run; --no-persist-report opts out; --report-format markdown-table
  renders the same shape on stdout.
• Plugin discovery: .claude/plugins/ and marketplace manifests are
  reported as Not Added with manual-setup notes.

Launch

• Cross-provider model translation between Claude/Codex families;
  Cursor and unknown models pass through untouched.
• Unified --plan flag translated to each tool's native syntax;
  unsupported tools error cleanly.

Init

• crossby init --install-skill installs the bundled crossby-sync skill
  into every detected tool's skills directory.

Behavior changes

• Codex agents path: .agents/ → .codex/agents/ (per upstream Codex
  docs). Legacy .agents/ is left untouched; a structlog warning fires.
• MCP Bearer rewrites for Codex: Authorization: Bearer ${VAR} becomes
  bearer_token_env_var = "VAR"; arbitrary ${VAR} headers become
  env_http_headers entries.

1437 unit tests, ruff clean, mypy strict clean.