Add webgl edge guard in texture getter

[maxkfranz]

Cross-references to related issues. If there is no existing issue that describes your bug or feature request, then create an issue before making your pull request.

Associated issues:

• Random "Script Error" thrown when generating nodes and edges in newest webgl version #3365

Notes re. the content of the pull request. Give context to reviewers or serve as a general record of the changes made. Add a screenshot or video to demonstrate your new feature, if possible.

• Adds a guard in ElementDrawingWebGL.drawTexture() for invalid edges.

Checklist

Author:

• The proper base branch has been selected. New features go on unstable. Bug-fix patches can go on either unstable or master.
• Automated tests have been included in this pull request, if possible, for the new feature(s) or bug fix. Check this box if tests are not pragmatically possible (e.g. rendering features could include screenshots or videos instead of automated tests).
• The associated GitHub issues are included (above).
• Notes have been included (above).
• For new or updated API, the index.d.ts Typescript definition file has been appropriately updated.

Reviewers:

• All automated checks are passing (green check next to latest commit).
• At least one reviewer has signed off on the pull request.
• For bug fixes: Just after this pull request is merged, it should be applied to both the master branch and the unstable branch. Normally, this just requires cherry-picking the corresponding merge commit from master to unstable -- or vice versa.

[Copilot]

Pull Request Overview

This PR adds validation for invalid edges in the WebGL renderer to prevent script errors when rendering edges with invalid geometry data. The change addresses issue #3365 where edges with invalid points were causing rendering errors.

• Introduces an edge validation guard in the texture drawing method
• Refactors existing edge validation logic into a reusable helper method
• Prevents rendering of edges with invalid geometric data (badLine, null allpts, or NaN coordinates)