Test tagging and filtering — run subsets of tests by label

[ThomasMalletCodra]

Description

Add the ability to assign tags/labels to individual tests (e.g., @slow, @hardware, @regression, @smoke) and filter test execution by tag. This allows users to run specific subsets of their test plan depending on the context (quick dev check vs. full qualification).

Current behavior

• All tests in a test plan are either run or not — no selective filtering.
• No tagging mechanism for individual test items.
• Users must manually select/deselect tests in the GUI to run subsets.

Expected behavior

• Tests can be tagged via # guitest: directives:

  # guitest: show
  # guitest: tags: smoke, fast
  def test_basic_functionality():
      ...

• Tags can also be assigned in moduletester.ini:

  [tags]
  tests/unit/ = unit, fast
  tests/integration/ = integration, slow
  tests/hardware/ = hardware, manual

• CLI filtering:

  moduletester -p mypackage.tests --tags smoke
  moduletester -p mypackage.tests --exclude-tags slow,hardware

• GUI filtering: tag filter bar/dropdown in the test plan view.
• Tags are displayed as badges next to test names in the UI.

Implementation ideas

1. Extend # guitest: parser to support a tags: directive.
2. Add tags field to TestItem model.
3. Add tag-based filtering in TestPlanModel.get_filtered_tests().
4. GUI: add a filter toolbar with tag chips/checkboxes.
5. CLI: add --tags and --exclude-tags arguments.

Acceptance criteria

• Tests can be tagged via # guitest: tags: directive
• Tests can be tagged via moduletester.ini configuration
• CLI supports --tags and --exclude-tags filtering
• GUI provides a tag filter in the test plan view
• Tags are displayed next to test names in the UI
• Multiple tags per test are supported