fix(installer): harden opencode recovery flow for WSL reinstall

docs(uninstall): add raw one-liner quickstart and README links

fix(installer): normalize runtime plugin path for OAuth menu

docs: publish uninstall parity contract and smoke checks

feat(uninstall): add safe/purge parity across bash and PowerShell

fix(installer): force /dev/tty for interactive setup fallback

fix(installer): harden headless fallback and WSL launcher path

fix(smoke): enforce antigravity oauth runtime prompt checks

docs(release): bump beta docs and changelog to v2.1.12

fix(installer): restore mac parity and harden auth fallback checks

chore(beta): rewire beta channel to beta sources

docs(readme): point private rollout commands to feat branch

feat(installer): align EXA/MCP flow for v2.1.11

docs(changelog): add missing v2.1.9 continuity entry

docs(readme): pin installer examples to v2.1.10