ci: fix fallback library jobs and add baikal integration tests

niquests is the default (not a fallback): async falls back to httpx,
sync falls back to requests.  The old async-niquests job was testing
the default path (already covered by the main matrix job) and not the
httpx fallback.

- Rename async-niquests → async-httpx; uninstall niquests so httpx is
  used; assert _USE_HTTPX in the verify step
- Add Baikal service + setup to both fallback jobs so integration tests
  run against a real server, not just unit/Radicale tests
- sync-requests: extend -k filter to "Baikal or Radicale" and pass
  BAIKAL_URL

prompt: There is no "niquests fallback" - niquests is the default
library now, with httpx as a fallback in async.  So we need 1) test
code to ensure the httpx fallback works in async mode, 2) test code to
ensure the requests fallback works in sync mode.  We should run both
sync tests and async tests towards the baikal server using niquests at
github.

AI Prompts:
claude-sonnet-4-6: There is no "niquests fallback" - niquests is the default library now, with httpx as a fallback in async.  So we need ... 1) test code to ensure the httpx fallback works in async mode, 2) test code to ensure the requests fallback works in sync mode.  We should run both sync tests and async tests towards the baikal server using niquests at github.

Author: tobixen

.github/workflows/tests.yaml

@@ -334,9 +334,9 @@ jobs:
           key: pip|${{ hashFiles('setup.py') }}|${{ hashFiles('tox.ini') }}
       - run: pip install tox
       - run: tox -e deptry
-  async-niquests:
-    # Test that async code works with niquests when httpx is not installed
-    name: async (niquests fallback)
+  async-httpx:
+    # Test that async code works with httpx when niquests is not installed
+    name: async (httpx fallback)
     runs-on: ubuntu-latest
     services:
       baikal:
@@ -354,10 +354,10 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-      - name: Install dependencies without httpx
+      - name: Install dependencies without niquests
         run: |
           pip install --editable .[test]
-          pip uninstall -y httpx
+          pip uninstall -y niquests
       - name: Configure Baikal with pre-seeded database
         run: |
           docker cp tests/docker-test-servers/baikal/Specific/. ${{ job.services.baikal.id }}:/var/www/baikal/Specific/
@@ -373,22 +373,33 @@ jobs:
             echo "✗ Error: Baikal did not become ready within 60 seconds"
             exit 1
           fi
-      - name: Verify niquests is used
+      - name: Verify httpx is used
         run: |
           python -c "
           from caldav.async_davclient import _USE_HTTPX, _USE_NIQUESTS
-          assert not _USE_HTTPX, 'httpx should not be available'
-          assert _USE_NIQUESTS, 'niquests should be used'
-          print('✓ Using niquests for async HTTP')
+          assert _USE_HTTPX, 'httpx should be available'
+          assert not _USE_NIQUESTS, 'niquests should not be available'
+          print('✓ Using httpx for async HTTP')
           "
-      - name: Run async tests with niquests
+      - name: Run async tests with httpx
         run: pytest tests/test_async_davclient.py tests/test_async_integration.py -v -k baikal
         env:
           BAIKAL_URL: http://localhost:8800
   sync-requests:
     # Test that sync code works with requests when niquests is not installed
     name: sync (requests fallback)
     runs-on: ubuntu-latest
+    services:
+      baikal:
+        image: ckulka/baikal:nginx
+        ports:
+          - 8800:80
+        options: >-
+          --health-cmd "curl -f http://localhost/ || exit 1"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+          --health-start-period 30s
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
@@ -399,6 +410,21 @@ jobs:
           pip install --editable .[test]
           pip uninstall -y niquests
           pip install requests
+      - name: Configure Baikal with pre-seeded database
+        run: |
+          docker cp tests/docker-test-servers/baikal/Specific/. ${{ job.services.baikal.id }}:/var/www/baikal/Specific/
+          docker cp tests/docker-test-servers/baikal/config/. ${{ job.services.baikal.id }}:/var/www/baikal/config/
+          docker exec ${{ job.services.baikal.id }} chown -R nginx:nginx /var/www/baikal/Specific /var/www/baikal/config
+          docker exec ${{ job.services.baikal.id }} chmod -R 770 /var/www/baikal/Specific
+          docker restart ${{ job.services.baikal.id }}
+      - name: Wait for Baikal to be ready
+        run: |
+          if timeout 60 bash -c 'until curl -f http://localhost:8800/ 2>/dev/null; do echo "Waiting..."; sleep 2; done'; then
+            echo "✓ Baikal is ready!"
+          else
+            echo "✗ Error: Baikal did not become ready within 60 seconds"
+            exit 1
+          fi
       - name: Verify requests is used
         run: |
           python -c "
@@ -408,4 +434,6 @@ jobs:
           print('✓ Using requests for sync HTTP')
           "
       - name: Run sync tests with requests
-        run: pytest tests/test_caldav.py -v -k "Radicale" --ignore=tests/test_async_integration.py
+        run: pytest tests/test_caldav.py -v -k "Baikal or Radicale" --ignore=tests/test_async_integration.py
+        env:
+          BAIKAL_URL: http://localhost:8800