fix(dashboard): paginate CEO dashboard ticket fetch to respect API cap

The CEO dashboard requested /api/tickets?page_size=500, but the API caps
page_size at 200 (le=200 in app/routers/tickets.py), so the request
returned 422 and every KPI/chart rendered zeros.

- ceo.html: fetch all tickets by looping pages of page_size=200 until
  total items are collected (with a safety bound), keeping KPIs accurate
  as volume grows past 200.
- tests: add test suite anchoring the pagination contract — page_size=500
  returns 422, page_size=200 returns items/total/page/page_size, and a
  page loop collects every ticket without duplicates.
- pyproject: enable pytest-asyncio auto mode and tests/ discovery.
- .gitignore: un-ignore committed tests/test_*.py.

pyproject.toml

@@ -22,6 +22,10 @@ build-backend = "setuptools.build_meta"
 [tool.setuptools.packages.find]
 include = ["app*"]
 
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+testpaths = ["tests"]
+
 [project.optional-dependencies]
 dev = [
     "pytest>=8.0",