Scaffold: package, settings, errors, server factory, shared contracts

protocol/types.py and arsdk/types.py are the interfaces the parallel streams
build against: command/arg/enum/expectation specs and the safety tiers on one
side, frame encoding and the buffer conventions on the other.

Logging goes to stderr throughout, since stdout carries JSON-RPC. That is also
why this package will speak ARSDK itself rather than through pyparrot, which
prints from its receive thread.

tests/test_packaging.py

@@ -0,0 +1,40 @@
+"""Guards that the package stays coherent as the streams land."""
+
+import tomllib
+from pathlib import Path
+
+import mcbebop
+from mcbebop.server import build_server
+
+
+def _pyproject() -> dict:
+    return tomllib.loads((Path(__file__).parent.parent / "pyproject.toml").read_text())
+
+
+def test_version_matches_pyproject():
+    # importlib normalises 2026.10.02 to 2026.10.2; compare as release tuples.
+    declared = _pyproject()["project"]["version"]
+    assert tuple(int(p) for p in declared.split(".")) == tuple(int(p) for p in mcbebop.__version__.split("."))
+
+
+def test_entry_point_is_importable():
+    module, _, attr = _pyproject()["project"]["scripts"]["mcbebop"].partition(":")
+    mod = __import__(module, fromlist=[attr])
+    assert callable(getattr(mod, attr))
+
+
+def test_server_builds():
+    assert build_server() is not None
+
+
+def test_vendored_xml_present_and_parses():
+    import xml.etree.ElementTree as ET
+
+    root = Path(__file__).parent.parent / "arsdk-xml"
+    total = 0
+    for name in ("common.xml", "ardrone3.xml"):
+        proj = ET.parse(root / name).getroot()
+        # Parrot's element is <class>; pyparrot renamed it and we reverted that.
+        assert proj.find("class") is not None, f"{name} has no <class> elements"
+        total += sum(len(c.findall("cmd")) for c in proj.iter("class"))
+    assert total == 264, f"expected 264 commands, found {total}"