fix(amazonq): Fix Q chat webview freezes & crash

[leigaol]

Problem

Q chat webview occasionally crashes.

Solution

1. Update mynahUI library.
2. At the same time, lift the size limit of symbols in context menu.

---

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[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
  • Confirm whether tests should be added or ensure the PR description explains why tests are not required.

[avi-alpert]

I will incorporate this into my own PR tomorrow

[avi-alpert]

Covered in PR: #6963