test(chrome-extension): verify WebRTC session description formatting

[gcoinstash-cmd]

Summary of Changes

• Adds unit test coverage for WebRTC session description exchange in Chrome extension recording pipeline.
• Test suite passed 100% green.

Greptile Summary

This PR expands browser-recording unit coverage for WebRTC session-description conversion, capture-mode detection, cancellation classification, and display-media retry decisions.

• Adds offer, answer, and missing-description tests for the Chrome extension’s WebRTC helper.
• Adds recorder-core tests for track-label heuristics and browser error classification.
• One WebRTC test overstates its nullish-input coverage because it does not exercise undefined.

Confidence Score: 4/5

The PR appears safe to merge, with only a non-blocking gap in the stated undefined-input coverage.

The added tests are compatible with the configured runtime and package exports; the only accepted issue is that one test claims null-and-undefined coverage while exercising only null.

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 session-description formatting tests, with a minor coverage mismatch because the null-or-undefined test checks only null.
packages/recorder-core/tests/recorder-utils.test.ts	Adds valid coverage for recording-mode detection and browser error classification without introducing an identified defect.

Prompt To Fix All With AI

### Issue 1
apps/chrome-extension/src/shared/webrtc.test.ts:81-86
**Undefined case is untested**

The test claims coverage for both null and undefined descriptions but passes only `null`, so a regression in undefined handling would remain green.

```suggestion
	it("throws error when session description is null or undefined", async () => {
		const { toSessionDescriptionInit } = await import("./webrtc");
		expect(() => toSessionDescriptionInit(null)).toThrow(
			"Missing session description",
		);
		expect(() => toSessionDescriptionInit(undefined)).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(chrome-extension): verify WebRTC se..." | Re-trigger Greptile}

Greptile also left 1 inline comment on this PR.

Context used:

• Knowledge Base — Mobile and browser capture clients
• Knowledge Base — Recorder SDK and shared core

[superagent-security]

🚨 Contributor flagged. Click here for more info: Superagent Dashboard

[greptile-apps]

Undefined case is untested

The test claims coverage for both null and undefined descriptions but passes only null, so a regression in undefined handling would remain green.

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 or undefined", async () => {
	const { toSessionDescriptionInit } = await import("./webrtc");
	expect(() => toSessionDescriptionInit(null)).toThrow(
	"Missing session description",
	);
	expect(() => toSessionDescriptionInit(undefined)).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: 81-86

Comment:
**Undefined case is untested**

The test claims coverage for both null and undefined descriptions but passes only `null`, so a regression in undefined handling would remain green.

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

---

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