Support Gemini CLI permissions

[saitota]

Creating this issue to track implementation status. If you'd like this feature, please upvote with 👍.

Refs #832

• Docs: https://geminicli.com/docs/reference/configuration/
• Enterprise: https://google-gemini.github.io/gemini-cli/docs/cli/enterprise.html
• Permissions schema PR: feat: add permissions schema definition and JSON Schema generation #1349