[codex] Keep Windows app checkouts on LF

[tianmind-studio]

Summary

• Add a scoped .gitattributes file under desktop/windows.
• Force text files in the Windows app subtree to check out with LF line endings.
• Keep Git checkout behavior aligned with the existing .editorconfig and Prettier setup.

Why

On this Windows checkout, desktop/windows files were written with CRLF because core.autocrlf=true. The Windows app already declares end_of_line = lf in .editorconfig, so ESLint/Prettier reported almost every line as Delete ␍, hiding the real lint findings.

This keeps the policy local to desktop/windows instead of changing the whole repository or weakening Prettier with endOfLine: auto.

Refresh

• Rebased on main at 9ed12aea07.
• Current head: be489b4a4d.

Validation

• git check-attr -a -- desktop/windows/electron.vite.config.ts desktop/windows/eslint.config.mjs desktop/windows/.prettierrc.yaml desktop/windows/src/renderer/src/lib/goals.test.ts -> text: auto, eol: lf for all four files.
• Fresh detached worktree from this branch with core.autocrlf=true:
  • desktop/windows/electron.vite.config.ts -> LF 26, CRLF 0
  • desktop/windows/eslint.config.mjs -> LF 32, CRLF 0
  • desktop/windows/src/renderer/src/lib/goals.test.ts -> LF 53, CRLF 0
  • desktop/windows/.prettierrc.yaml -> LF 4, CRLF 0
  • root README.md remained CRLF 174, showing the rule is scoped.
• Fresh-checkout files with local Windows app Prettier: prettier --check electron.vite.config.ts eslint.config.mjs .prettierrc.yaml src/renderer/src/lib/goals.test.ts -> passed.
• git diff --check origin/main...HEAD
• C:\\Program Files\\Git\\bin\\sh.exe -c 'scripts/pre-commit'