Clean up dry run artifacts and fix content consistency

- Remove generated workflow, action, infra, and azure files from dry run
- Remove test change from server/app.py
- Fix duplicate step numbering in module 7
- Fix typo in module 8 ('n' → 'in')
- Convert non-action numbered items to prose (modules 7, 8)
- Reset step numbering at section boundaries (module 4)
- Standardize Resources heading to h2 across all modules
- Add tests-passed summary job exercise to module 9

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: GeekTrainer

.github/actions/setup-python-env/action.yml

@@ -106,7 +106,7 @@ Congratulations! You've created and run your first GitHub Actions workflow. You'
 
 Next, we'll put this knowledge to work by [securing the development pipeline][walkthrough-next] with code scanning, Dependabot, and secret scanning.
 
-### Resources
+## Resources
 
 - [GitHub Actions documentation][github-actions-docs]
 - [Workflow syntax for GitHub Actions][workflow-syntax]

.github/workflows/azure-dev.yml

@@ -95,7 +95,7 @@ You've enabled GitHub Advanced Security for your repository:
 
 These tools run automatically in the background, catching security issues before they reach production. Now that you've seen how GitHub uses Actions internally for security automation, it's time to build your own CI workflow. Next, we'll [automate testing][walkthrough-next] for the shelter's application.
 
-### Resources
+## Resources
 
 - [About GitHub Advanced Security][advanced-security-docs]
 - [About code scanning with CodeQL][about-code-scanning]

.github/workflows/hello.yml

@@ -174,7 +174,7 @@ You've built a CI pipeline with two jobs running in parallel — unit tests for
 
 Now, let's work to [improve the performance of our CI job][walkthrough-next] by reusing steps and caching dependencies.
 
-### Resources
+## Resources
 
 - [GitHub Actions documentation][github-actions-docs]
 - [Workflow syntax for GitHub Actions][workflow-syntax]