support explicit event push and hybrid for more cases

[kibertoad]

Changes

Support pushing events on demand and support hybrid mode for more use-cases

Checklist

• Apply one of following labels; major, minor, patch or skip-release
• I've updated the documentation, or no changes were necessary
• I've updated the tests, or no changes were necessary

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📝 Walkthrough

Walkthrough

The PR adds Server-Sent Events (SSE) mocking capabilities to the universal testing utilities library. A new mockSseStream API is introduced that returns an SseEventController for on-demand SSE event emission. The existing mockValidResponseWithImplementation method is extended to support dual-mode contracts that route requests based on the Accept header, serving either JSON responses via handleRequest or SSE streams. Documentation is updated to reflect these additions, and comprehensive test coverage is included for both new APIs and existing functionality under dual-mode scenarios.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately reflects the main changes: adding support for on-demand event pushing (mockSseStream) and extending hybrid/dual-mode support to more cases (mockValidResponseWithImplementation for dual-mode).
Description check	✅ Passed	The description includes all required template sections: Changes section describing the work, completed Checklist with release label and update confirmations, and AI Assistance Tracking with appropriate selection.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/app/universal-testing-utils/src/MswHelper.ts`:
- Around line 489-494: The REST branch handler registered with server.use using
http[method] passes params.responseCode directly to HttpResponse.json which can
be undefined; update that call in the http[method](...) handler to supply a
default (e.g. params.responseCode ?? 200) so the status is guaranteed, keeping
the same request handling via params.handleRequest and HttpResponse.json.

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📥 Commits

Reviewing files that changed from the base of the PR and between d3fff12 and 625ea86.

📒 Files selected for processing (4)

• packages/app/universal-testing-utils/README.md
• packages/app/universal-testing-utils/src/MswHelper.spec.ts
• packages/app/universal-testing-utils/src/MswHelper.ts
• packages/app/universal-testing-utils/src/index.ts

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Missing default for responseCode in REST branch.

The dual-mode branch uses params.responseCode ?? 200, but the REST branch passes params.responseCode directly without a default. If responseCode is undefined, this passes undefined to HttpResponse.json, which may cause unexpected behavior.

🔧 Proposed fix

       server.use(
         http[method](resolvedPath, async (requestInfo) => {
           return HttpResponse.json(await params.handleRequest(requestInfo), {
-            status: params.responseCode,
+            status: params.responseCode ?? 200,
           })
         }),
       )

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	server.use(
	http[method](resolvedPath, async (requestInfo) => {
	return HttpResponse.json(await params.handleRequest(requestInfo), {
	status: params.responseCode,
	})
	}),
	server.use(
	http[method](resolvedPath, async (requestInfo) => {
	return HttpResponse.json(await params.handleRequest(requestInfo), {
	status: params.responseCode ?? 200,
	})
	}),

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@packages/app/universal-testing-utils/src/MswHelper.ts` around lines 489 -
494, The REST branch handler registered with server.use using http[method]
passes params.responseCode directly to HttpResponse.json which can be undefined;
update that call in the http[method](...) handler to supply a default (e.g.
params.responseCode ?? 200) so the status is guaranteed, keeping the same
request handling via params.handleRequest and HttpResponse.json.