fix(app): make client ID generation resilient to UUID failures

[Jacobinwwey]

1. Context & Motivation (Context)

• Issue: N/A
• Problem: The app currently assumes globalThis.crypto.randomUUID() is always usable when minting a client ID. On some React Native / Expo setups the UUID path can be broken or recurse through an incomplete polyfill, which turns first-run client ID creation into a hard failure instead of a recoverable fallback.
• Trade-offs: This change keeps randomUUID() as the preferred entropy source, but falls back to getRandomValues() when UUID generation is broken. That adds a small amount of local formatting logic in exchange for a more robust startup path without changing the persisted client ID shape.

2. Implementation Details (Implementation)

• Updated client-id generation to catch randomUUID() failures and derive the persisted identifier from getRandomValues() before falling back to the existing time/Math-based path.
• Updated the Expo crypto polyfill to synthesize randomUUID() from getRandomValues() so environments that already expose a working random byte source do not depend on a second UUID implementation.
• Added regression coverage for both the client ID path and the crypto polyfill path.
• Note: This intentionally avoids any Metro / Expo workspace resolution changes. The PR is limited to runtime fallback behavior and its tests.

3. Testing Strategies (Validation)

• Added Unit Tests for client-id (covering randomUUID() failure fallback)
• Added Unit Tests for polyfillCrypto (covering non-recursive UUID generation from getRandomValues())
• Ran npm run test --workspace=@getpaseo/app -- src/utils/client-id.test.ts src/polyfills/crypto.test.ts
• Ran npm run build:highlight && npm run typecheck --workspace=@getpaseo/app
• Verified backward compatibility with the existing cid_<hex> storage format