test(utils): cover generateId's insecure-context fallback

[reddynitish]

Summary

• Issue [Bug] White screen / "Application error" - crypto.randomUUID is not a function #3393 reports a white-screen crash on self-hosted deployments accessed over plain HTTP (a LAN IP, not localhost/HTTPS): TypeError: crypto.randomUUID is not a function. Browsers only expose crypto.randomUUID() in secure contexts.
• This is already fixed on current staging — generateId() (packages/utils/src/id.ts) has feature-detected crypto.randomUUID and fallen back to a crypto.getRandomValues()-based UUID v4 since b5674d9ed4 (improvement(codebase): centralize test mocks, extract @sim/utils, remove dead code #4228). A repo-wide grep confirms no client-side code in apps/sim calls crypto.randomUUID directly anymore, and scripts/check-utils-enforcement.ts bans direct usage outside that one definition file. This PR does not fix a bug — nothing here changes production behavior.
• What it does close: the existing test suite for generateId() only ever exercised the "happy path" — Node/Bun's crypto.randomUUID is always present in the test environment, so the fallback branch that actually fixes [Bug] White screen / "Application error" - crypto.randomUUID is not a function #3393 had zero coverage. A future refactor could silently reintroduce the exact crash with nothing catching it.
• Adds two tests to packages/utils/src/id.test.ts that stub crypto.randomUUID to undefined (restored in afterEach, verified not to leak across tests or files) and assert generateId() still returns a valid, unique UUID v4. Verified these tests genuinely fail with the original TypeError when generateId() is temporarily reverted to a naive crypto.randomUUID() call, and pass again once restored.

Refs #3393 (using Refs, not Fixes — the underlying bug isn't something this PR resolves; it already isn't reproducible on staging).

Type of Change

• Other: test-only regression coverage for an already-fixed bug

Testing

• cd packages/utils && bunx vitest run src/id.test.ts — PASS, 12/12.
• Reverted generateId() to the pre-fix return crypto.randomUUID() (no guard) and re-ran the same file — the two new tests failed with TypeError: crypto.randomUUID is not a function, the exact error from [Bug] White screen / "Application error" - crypto.randomUUID is not a function #3393; all other tests still passed. Restored the file and confirmed git diff clean before committing.
• cd packages/utils && bunx vitest run (full workspace, all 14 files) — PASS, 194/194, both before and after the regression check above — the afterEach restore doesn't leak across tests or files.
• bunx tsc --noEmit / bunx turbo run type-check --filter=@sim/utils — PASS. Confirms the two @ts-expect-error directives suppress a real type error rather than being stale (an unused directive is itself a type error).
• bunx biome check packages/utils/src/id.test.ts — PASS.
• bun run check:utils — pre-existing baseline failures only (13 hits, all in files already on the allowlist — id.ts's own definition, helpers.ts, random.ts, etc.); none are in id.test.ts, which is already allowlisted at scripts/check-utils-enforcement.ts:37 for referencing the banned pattern directly (needed to test it).
• Full grep of apps/sim for crypto.randomUUID / randomUUID — 6 hits, all vi.fn() test mocks; zero production callsites.

An independent adversarial review (Claude subagent, no session context, in place of Codex which isn't installed on this machine) reproduced all of the above itself — including a stress test running the full suite with --no-isolate --no-file-parallelism to rule out cross-file leakage from the crypto.randomUUID stub — and confirmed the diff is correct as-is. It also independently traced the fix to b5674d9ed4 and flagged that the PR should be framed as coverage rather than a fix (reflected above), which is the only change it asked for.

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)

Screenshots/Videos

N/A — test-only change, no UI.

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[greptile-apps]

Greptile Summary

This PR adds regression coverage for generateId() when crypto.randomUUID is unavailable, without changing production behavior.

• Adds fallback-path UUID v4 validation.
• Verifies fallback-generated IDs remain unique across 100 calls.
• Restores the global crypto method after each test to preserve isolation.

Confidence Score: 5/5

The test-only change appears safe to merge.

The new tests exercise the existing fallback path and restore the temporarily modified crypto method after every test, with no production-code changes or accepted defects.

Important Files Changed

Filename	Overview
packages/utils/src/id.test.ts	Adds focused, isolated tests for the existing insecure-context UUID fallback; no actionable issues found.

_{Reviews (1): Last reviewed commit: "test(utils): cover generateId's insecure..." | Re-trigger Greptile}