chore: Added generated lang headers to .gitignore (#1158)

## Summary

**What is the goal of this PR?**

Following up on #1156: generated language header files should be
ignored.

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### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? _**NO**_