docs: cookbook expansion and learning path improvements

[Tuntii]

This PR updates the RustAPI documentation as part of the scheduled maintenance run.

Key changes:

1. Fixes: Corrected MockServer examples in recipes/testing.md which were using incorrect async syntax and nonexistent methods.
2. New Content: Added a comprehensive "Graceful Shutdown" recipe covering CTRL+C and SIGTERM handling.
3. Learning Path: Expanded Module 11 to include a concrete mini-project ("The Email Worker") and better knowledge checks.
4. Tracking: Updated agent run report and coverage map.

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PR created automatically by Jules for task 12444186712278693427 started by @Tuntii

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[Copilot]

Pull request overview

This PR updates the RustAPI documentation with fixes, new content, and learning path improvements. The changes primarily focus on correcting MockServer examples, adding a comprehensive graceful shutdown guide, and enhancing the background jobs module in the learning curriculum.

Changes:

• Fixed MockServer API usage in testing recipe (removed incorrect .await and replaced nonexistent url() method)
• Added new "Graceful Shutdown" recipe covering signal handling and run_with_shutdown API
• Enhanced Module 11 of the learning curriculum with a mini-project and improved knowledge checks

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
docs/cookbook/src/recipes/testing.md	Fixed MockServer example to use correct API (removed .await on builder, use base_url() + format string)
docs/cookbook/src/recipes/graceful_shutdown.md	New comprehensive recipe for graceful shutdown with CTRL+C and SIGTERM handling
docs/cookbook/src/recipes/README.md	Added link to new Graceful Shutdown recipe
docs/cookbook/src/learning/curriculum.md	Enhanced Module 11 with "The Email Worker" mini-project and better knowledge checks
docs/cookbook/src/SUMMARY.md	Added Graceful Shutdown to table of contents
docs/.agent/run_report_2026-02-23.md	New run report documenting the changes
docs/.agent/last_run.json	Updated last run metadata
docs/.agent/docs_coverage.md	Added Graceful Shutdown entry to coverage map

Comments suppressed due to low confidence (1)

docs/cookbook/src/recipes/testing.md:115

• The MockServer test is missing a verification call at the end. According to the rustapi-testing implementation, MockServer does not auto-verify expectations on Drop; tests must explicitly call mock_server.verify() at the end to ensure that all expectations were met. Add mock_server.verify(); after the assertions to complete the test properly.

async fn test_external_integration() {
    // 1. Start a mock server
    let mock_server = MockServer::start().await;

    // 2. Define an expectation
    mock_server.expect(
        rustapi_testing::RequestMatcher::new()
            .method("GET")
            .path("/external-data")
    ).respond_with(
        MockResponse::new()
            .status(200)
            .body(r#"{"data": "mocked"}"#)
    );

    // 3. Use the mock server's URL in your app configuration
    let mock_url = format!("{}{}", mock_server.base_url(), "/external-data");

    // Simulating your app logic calling the external service
    let client = reqwest::Client::new();
    let res = client.get(&mock_url).send().await.unwrap();

    assert_eq!(res.status(), 200);
    let body = res.text().await.unwrap();
    assert_eq!(body, r#"{"data": "mocked"}"#);
}

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[Copilot]

The API usage mentioned here is incorrect. The rustapi-jobs library doesn't have a JobWorker type. Based on the actual implementation in crates/rustapi-jobs/src/queue.rs, the correct way to start the worker loop is to call queue.start_worker().await where queue is a JobQueue instance. The pitfall should read: "Forgetting to start the job worker loop (spawn queue.start_worker().await in a background task)".

Suggested change

	- **Pitfalls:** Forgetting to start the job worker loop (`JobWorker::new(queue).run().await`).
	- **Pitfalls:** Forgetting to start the job worker loop (spawn `queue.start_worker().await` in a background task).

[Copilot]

The production example references a hello function on line 59, but this function is not defined in this code block. The example should either include the hello function definition (copying it from the basic example) or use an inline closure instead, such as .route("/", get(|| async { "Hello" })), to make the example self-contained and compilable.