[yukuai26]

Remove the formatting and lint tooling, including the GitHub Actions workflow and local check script.

• Remove the Code Format Check workflow and format.sh.
• Remove the clang-format, YAPF, and Ruff dependencies and configurations.
• Keep .editorconfig unchanged.
• No functional code changes or repository-wide reformatting.

Validation:

• git diff --check passed.
• Verified that no references to the removed tooling remain in tracked files, apart from the harmless .editorconfig filename pattern.
• No tracked GitHub Actions workflows remain on this branch.