feat(cli): add offline config check

[EzraCerpac]

Summary

• add rift config check --config PATH
• parse the full config and run semantic validation without starting Rift
• resolve hotkeys through a static offline map so the command never touches AppKit, Accessibility, WindowServer, Carbon keyboard-layout services, startup commands, or Rift services
• reject layout-specific character keys that cannot be proven valid offline with a clear error

Tests

• cargo test --locked common::config_check
• cargo test --locked sys::hotkey::tests
• cargo build --locked --bin rift
• target/debug/rift config check --config rift.default.toml

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-29T19:46:35.186428Z	aecaadb	New commits

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