fix(scripts): enforce LF line endings for shell scripts #1610

Windows checkouts can convert tracked shell scripts to CRLF when Git uses core.autocrlf=true. ShellCheck then reports SC1017 on affected lines, creating widespread editor diagnostics even though the indexed scripts use LF.

Component

Development Environment

Steps to Reproduce

1. Configure Git with core.autocrlf=true on Windows.
2. Check out the repository without a shell-specific line-ending policy.
3. Open a tracked .sh file in VS Code with ShellCheck diagnostics enabled.
4. Observe SC1017 literal carriage-return errors.

Expected Behavior

Tracked .sh files use LF in the worktree regardless of the contributor's global Git line-ending configuration.

Environment

• OS: Windows
• Git setting: core.autocrlf=true
• Editor: Visual Studio Code

Error Output

Literal carriage return. Run script through tr -d '\r' .

Acceptance Criteria

• The root .gitattributes file declares *.sh text eol=lf.
• .gitattributes is not excluded by .gitignore.
• Every tracked .sh file resolves to text: set and eol: lf.
• Normalization introduces no shell source-content drift.
• Workspace diagnostics contain no SC1017 errors after files reload from disk.