Extract reusable device protocols, ports and logic analyzers from SETGUI

python/set_devices/shared_protocol.py

@@ -0,0 +1,18 @@
+"""Optional native SETProtocol backend, configured by SETPROTOCOL_LIBRARY."""
+
+from __future__ import annotations
+
+def _load():
+    try:
+        from protocan.native import NativeProtocol
+        return NativeProtocol()
+    except (ImportError, OSError, RuntimeError):
+        return None
+
+
+SHARED_PROTOCOL = _load()
+
+
+def get_shared_protocol():
+    """Return SETProtocol, or None for source/test fallback builds."""
+    return SHARED_PROTOCOL