chore: sync upstream v1.3.16

Sync 10 upstream commits from anomalyco/opencode including v1.3.16 release.

## Changes to merge
- Cloudflare provider env error fix
- Azure provider fix
- Mouse disable feature
- Windows Ctrl+Z tip
- Plugin specifier parsing fix
- ACP configOptions
- Nix hashes update
- Zen rate limiter normalization

## Fork preservation
- notifications feature
- guardrails package
- fork workflows