feat(hooks): add Trae IDE integration

[deqingLv]

Summary

• add --agent trae project and global install/uninstall support for Trae hooks.json
• add a native rtk hook trae adapter that transparently rewrites RunCommand inputs through RTK while preserving Trae's permission flow
• document Trae setup, payload format, global .trae / .trae-cn behavior, and add coverage for config preservation, idempotency, backup, uninstall, and malformed input

Behavior

• project install: rtk init --agent trae writes .trae/hooks.json
• global install: rtk init -g --agent trae always manages ~/.trae/hooks.json and additionally manages ~/.trae-cn/hooks.json when ~/.trae-cn already exists
• existing config and unrelated hooks are preserved; existing files are backed up before mutation
• uninstall removes only RTK-managed nested hooks
• the native handler returns hookSpecificOutput.updatedInput and deliberately omits permissionDecision, leaving approval policy to Trae

Test plan

• cargo fmt --all --check && cargo clippy --all-targets && cargo test
• Full suite: 2451 unit tests passed, 8 ignored; all integration test binaries passed
• Manual testing: project install and uninstall in an isolated temporary directory
• Manual testing: Trae PreToolUse payload rewrote git status to rtk git status while preserving the description field

[CLAassistant]

All committers have signed the CLA.

[tapheret2]

Review: feat(hooks): add Trae IDE integration

Files: README.md, README_es.md, README_fr.md, README_ja.md, README_ko.md
Size: +853 / -22

Notes

• Static pass on the patch: no obvious blockers from the diff alone.

Thanks @deqingLv — independent review on the patch.