Fix: Vitest related security vulnerability

[b1ink0]

Description

This PR fixes Vitest and Babel-related security vulnerabilities by updating them to patched versions and overriding vulnerable transitive dependencies.

It also updates the Vite configuration to support the major version upgrade of Vitest.

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Checklist

• I have thoroughly tested this code to the best of my abilities.
• I have reviewed the code myself before requesting a review.
• This code is covered by unit tests to verify that it works as intended.
• The QA of this PR is done by a member of the QA team (to be checked by QA).

Fixes:

• https://github.com/rtCamp/frappe-ui-react/security/dependabot/44
• https://github.com/rtCamp/frappe-ui-react/security/dependabot/40

[Copilot]

Pull request overview

This PR addresses reported security vulnerabilities in the toolchain by upgrading Vitest (major version bump) and Babel presets, and by adding PNPM overrides for vulnerable transitive dependencies. It also adjusts the Vite/Vitest browser testing configuration to align with the Vitest upgrade.

Changes:

• Upgrade Vitest to 4.1.8 and adjust the Vitest browser provider configuration in vite.config.ts.
• Upgrade Babel presets to ^7.29.5.
• Add/adjust PNPM overrides (e.g., brace-expansion, vitest, ws) and update pnpm-lock.yaml accordingly.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
vite.config.ts	Updates Vitest browser provider configuration for the Vitest major upgrade.
package.json	Bumps Vitest/Babel-related devDependencies and adds/updates PNPM override rules for vulnerable transitive deps.
pnpm-lock.yaml	Lockfile refresh reflecting the dependency upgrades and override-driven resolutions.