[Security] Harden client ID generation

[gonzaloriestra]

WHY are these changes introduced?

Hardens the generation of client identifiers to prevent predictability.

WHAT is this pull request doing?

Replaces Math.random() with globalThis.crypto.randomUUID() for generating client IDs in ExtensionServerClient. This ensures that IDs are cryptographically secure when the environment supports it.

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 8128284611905294970 started by @gonzaloriestra

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