OpenCode Permission Reviewer

The reviewer policy design is inspired by OpenAI Codex Guardian:

  https://github.com/openai/codex/tree/main/codex-rs/core/src/guardian

The policy wording and implementation are independent. The plugin adds
OpenCode permission semantics, human escalation, confidence validation,
isolated review, and SSH, local-script, and Git evidence enrichment.

OpenAI Codex is Copyright OpenAI and contributors and is licensed under the
Apache License, Version 2.0. This project is licensed under the Apache License,
Version 2.0 (see ./LICENSE).