Support Flutter 3.38 and refresh package release

[mehedi8603651]

Summary

• add Flutter 3.38 / Dart 3.10 compatibility updates and remove deprecated API usage
• fix current selection toolbar and focus behavior, plus a few parser/rendering bugs
• refresh dependency constraints, release docs, example metadata, and golden assets

Notes

• SelectableMath now uses SelectableMathToolbarOptions instead of Flutter's deprecated ToolbarOptions
• direct meta dependency was removed because the Flutter SDK currently pins it through flutter_test

Validation

• flutter analyze
• flutter test
• flutter analyze in example/

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: e1503f13-d9c0-43fb-a9df-1f5886a50143

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}