[Security] Hardened client ID generation

[gonzaloriestra]

WHY are these changes introduced?

The current implementation uses Math.random() to generate a client ID, which is not cryptographically secure and can be predictable.

WHAT is this pull request doing?

This pull request replaces the insecure Math.random() based ID generation with globalThis.crypto.randomUUID() when available, providing a more secure and unique identifier. A safe fallback is maintained for environments where the crypto API is not supported.

How to test your changes?

CI

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes
• I've considered analytics changes to measure impact
• The change is user-facing — I've identified the correct bump type (patch for bug fixes · minor for new features · major for breaking changes) and added a changeset with pnpm changeset add

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PR created automatically by Jules for task 3125192890537652369 started by @gonzaloriestra

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