Remove mypy_zope, update CI for pytest, and add newsfile.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: sandhose

.github/workflows/pipeline.yml

@@ -33,7 +33,7 @@ jobs:
 
       - uses: astral-sh/setup-uv@v5
 
-      - run: uv run python -m twisted.trial tests
+      - run: uv run pytest tests/
 
   run-unit-tests-olddeps:
     name: Unit tests (old dependencies)
@@ -50,4 +50,4 @@ jobs:
           diff pyproject.toml.bak pyproject.toml || true
       - name: Install Sygnal
         run: python -m pip install -e .
-      - run: python -m twisted.trial tests
+      - run: python -m pytest tests/

changelog.d/454.removal

@@ -0,0 +1 @@
+Replace Twisted with aiohttp and native asyncio.

mypy.ini

@@ -1,5 +1,4 @@
 [mypy]
-plugins = mypy_zope:plugin
 check_untyped_defs = True
 disallow_untyped_defs = True
 show_error_codes = True
@@ -39,5 +38,3 @@ disallow_untyped_defs = False
 [mypy-tests.twisted_test_helpers]
 disallow_untyped_defs = False
 
-[mypy-sygnal.helper.proxy.proxyagent_twisted]
-ignore_errors = True