build: add deps and test scaffolding for auto-reverse

Adds runtime deps (playwright, mitmproxy, anthropic, genson) and dev
deps (pytest, pytest-asyncio); creates the tests/ scaffold with
fixture_site.py, conftest.py, and a smoke test. Documents the
mitmproxy aioquic/mitmproxy-rs stub workaround needed for
free-threaded CPython 3.14.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -7,7 +7,12 @@ authors = [
     { name = "Wong Ding Feng", email = "dingfengwong@gmail.com" }
 ]
 requires-python = ">=3.14"
-dependencies = []
+dependencies = [
+    "anthropic>=0.105.2",
+    "genson>=1.3.0",
+    "mitmproxy>=12.2.3",
+    "playwright>=1.60.0",
+]
 
 [project.scripts]
 auto-reverse = "auto_reverse:main"
@@ -28,3 +33,19 @@ pythonVersion = "3.14"
 typeCheckingMode = "strict"
 venvPath = "."
 venv = ".venv"
+
+[tool.uv]
+override-dependencies = [
+    "aioquic @ file:///tmp/aioquic-stub",
+    "mitmproxy-rs @ file:///tmp/mitmproxy-rs-stub",
+]
+
+[dependency-groups]
+dev = [
+    "pytest>=9.0.3",
+    "pytest-asyncio>=1.4.0",
+]
+
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+testpaths = ["tests"]