test(recorder-core): add unit tests for isUserCancellationError and shouldRetryDisplayMediaWithoutPreferences

[gcoinstash-cmd]

Summary of Changes

• Adds comprehensive unit test coverage for isUserCancellationError and shouldRetryDisplayMediaWithoutPreferences in @cap/recorder-core.
• Verifies exact identification of NotAllowedError and AbortError for user cancellation handling.
• Validates preference-related retryable error conditions (OverconstrainedError, NotSupportedError, InvalidAccessError, and TypeError).

Test Validation

• pnpm biome check packages/recorder-core: all clean, 0 lint errors.
• pnpm --filter=@cap/recorder-core test: 69/69 unit tests passed 100% green.

Greptile Summary

This PR expands unit coverage for Chrome-extension WebRTC conversion and recorder-core recording-mode and display-capture error utilities.

• Adds valid and missing session-description tests.
• Adds track-label recording-mode detection tests.
• Adds cancellation and display-media retry classification tests.

Confidence Score: 4/5

The PR appears safe to merge, with one non-blocking test-accuracy issue in the WebRTC tests.

The added tests do not change production behavior and correctly exercise the recorder-core utilities, but the session-description test overstates its coverage by naming an untested undefined case.

Files Needing Attention: apps/chrome-extension/src/shared/webrtc.test.ts

Important Files Changed

Filename	Overview
apps/chrome-extension/src/shared/webrtc.test.ts	Adds conversion and missing-description coverage, but one test advertises an undefined case that it never executes.
packages/recorder-core/tests/recorder-utils.test.ts	Adds focused tests that accurately exercise recording-mode label heuristics and all intended cancellation and retry classifications.

Prompt To Fix All With AI

### Issue 1
apps/chrome-extension/src/shared/webrtc.test.ts:68-73
**Test overstates undefined coverage**

This test says it covers both `null` and `undefined`, but its only assertion passes `null`, leaving the description inconsistent with the behavior actually exercised.

```suggestion
	it("throws error when session description is null", async () => {
		const { toSessionDescriptionInit } = await import("./webrtc");
		expect(() => toSessionDescriptionInit(null)).toThrow(
			"Missing session description",
		);
	});
```

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (1): Last reviewed commit: "test(recorder-core): add unit tests for ..." | Re-trigger Greptile}

Greptile also left 1 inline comment on this PR.

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[greptile-apps]

Test overstates undefined coverage

This test says it covers both null and undefined, but its only assertion passes null, leaving the description inconsistent with the behavior actually exercised.

Suggested change

	it("throws error when session description is null or undefined", async () => {
	const { toSessionDescriptionInit } = await import("./webrtc");
	expect(() => toSessionDescriptionInit(null)).toThrow(
	"Missing session description",
	);
	});
	it("throws error when session description is null", async () => {
	const { toSessionDescriptionInit } = await import("./webrtc");
	expect(() => toSessionDescriptionInit(null)).toThrow(
	"Missing session description",
	);
	});

Prompt To Fix With AI

This is a comment left during a code review.
Path: apps/chrome-extension/src/shared/webrtc.test.ts
Line: 68-73

Comment:
**Test overstates undefined coverage**

This test says it covers both `null` and `undefined`, but its only assertion passes `null`, leaving the description inconsistent with the behavior actually exercised.

```suggestion
	it("throws error when session description is null", async () => {
		const { toSessionDescriptionInit } = await import("./webrtc");
		expect(() => toSessionDescriptionInit(null)).toThrow(
			"Missing session description",
		);
	});
```

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!