Add a script to validate & fix mismatches CRLF in the repo

[OneBlue]

Summary of the Pull Request

This change adds a script that blocks merging a change with mismatches CRLF in code files. clang-format does some of it, but it doesn't cover all files.

The files can be fixed via python tools/devops/validate-line-endings.py . --fix

This will prevent needless git conflicts and copilot getting confused

PR Checklist

• Closes: Link to issue #xxx
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated if needed and all pass
• Localization: All end user facing strings can be localized
• Dev docs: Added/updated if needed
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Validation Steps Performed

[Copilot]

Pull request overview

Adds a repo validation script intended to detect (and optionally fix) non-CRLF line endings in tracked source files, and wires it into CI to prevent line-ending churn and merge conflicts.

Changes:

• Added tools/devops/validate-line-endings.py to detect line-ending mismatches and optionally normalize files to CRLF.
• Updated the build pipeline checks stage to run a line-ending validation step (intended).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
tools/devops/validate-line-endings.py	New Python validator to detect/fix non-CRLF line endings for selected tracked source files.
.pipelines/build-stage.yml	Adds a CI “line feeds” check step (currently wired to the wrong script).