feat!: v0.2.0 — PyPI-ready, interception tests, strict linting

PyPI-ready metadata (donglora-mux), full classifiers, URLs.
Fixed dependency path to client-py. Added 11 interception tests
ported from the Rust mux (SetConfig locking, StartRx/StopRx
refcounting). GitHub Actions CI. Strict ruff linting.

Applied contextlib.suppress per SIM105, collapsed nested ifs per
SIM102.

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

justfile

@@ -14,8 +14,8 @@ run *args: _ensure_tools
 verbose *args: _ensure_tools
     @uv run -m donglora_mux --verbose {{args}}
 
-# Run all checks (fmt, lint)
-check: fmt-check lint
+# Run all checks (fmt, lint, test)
+check: fmt-check lint test
 
 # Format code
 fmt: _ensure_tools
@@ -28,3 +28,7 @@ fmt-check: _ensure_tools
 # Lint
 lint: _ensure_tools
     @uv run ruff check .
+
+# Run tests
+test: _ensure_tools
+    @uv run pytest -v