[Security] Harden ExtensionServerClient random identifier generation

[gonzaloriestra]

WHY are these changes introduced?

Hardens the random identifier generation in ExtensionServerClient by utilizing a cryptographically secure pseudo-random number generator (CSPRNG).

WHAT is this pull request doing?

Replaces the insecure Math.random() call used to generate this.id in ExtensionServerClient with a new generateRandomId utility. This utility leverages globalThis.crypto.randomUUID where available to ensure unpredictability and falls back to a pseudo-random math string in non-secure or older environments.

How to test your changes?

CI

Post-release steps

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 1037256159771227403 started by @gonzaloriestra

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