[deevus]

Summary

Adds gdzig-zlint (ZLint 0.10.0 with the gdzig CODE_STYLE rules) and wires it into mise and CI. Follow-up to gdzig/gdzig#290.

• Installs github:gdzig/gdzig-zlint 0.6.1 through mise.toml; mise.lock gains the checksummed release entries. The existing Zig dev pin is unchanged.
• Adds zlint.json from the 0.6.1 template. Mechanically enforceable gdzig rules are error; gdzig-public-docs and line-length use the template's warn level.
• Adds mise run lint and a Lint workflow that runs on pull requests, pushes to main, and manual dispatch.
• Applies the rules across the tree: import sorting and placement.

Verification

• gdzig-zlint .: 0 errors, 6 warnings (before: 0 errors, 8 warnings).
• zig build test: passes.
• zig fmt --check build.zig tests.zig: passes.
• Remaining warnings: 3 gdzig-public-docs and 3 line-length.

Notes

• --deny-warnings is intentionally not enabled yet because the existing documentation and line length diagnostics still need cleanup.
• This repository has no pre-commit or hk configuration, so no hook was added.