Set element.ndi_element_class to match MATLAB class(self) behavior

MATLAB's element.newdocument() sets element.ndi_element_class to
class(ndi_element_obj), which returns the MATLAB class name (e.g.
"ndi.element", "ndi.probe.timeseries.mfdaq"). Python was leaving this
as the schema default "ndi_element".

Changes:
- Element: Add ndi_element_class() returning "ndi.element", set it
  in newdocument()
- Probe: Override ndi_element_class() to use probetype2object.json
  mapping (e.g. "n-trode" -> "ndi.probe.timeseries.mfdaq"), remove
  redundant newdocument() override (inherit from Element like MATLAB)
- Element.searchquery(): Match MATLAB's query which includes name,
  type, ndi_element_class, and reference (was only base.id)

https://claude.ai/code/session_01RBSaNF8SSrGqnpnP5vUT47

Author: claude

src/ndi/element/__init__.py

@@ -183,6 +183,20 @@ def dependencies(self) -> dict[str, str]:
         """Get additional dependencies."""
         return self._dependencies
 
+    def ndi_element_class(self) -> str:
+        """Return the NDI element class name for document storage.
+
+        MATLAB equivalent: ``class(ndi_element_obj)``
+
+        Returns the MATLAB-compatible class name string used in the
+        ``element.ndi_element_class`` document field.  Subclasses
+        override this to return their own class name.
+
+        Returns:
+            MATLAB class name string, e.g. ``'ndi.element'``.
+        """
+        return "ndi.element"
+
     def elementstring(self) -> str:
         """
         Format element as human-readable string.
@@ -393,6 +407,7 @@ def newdocument(self) -> Any:
         doc = Document(
             "element",
             **{
+                "element.ndi_element_class": self.ndi_element_class(),
                 "element.name": self._name,
                 "element.reference": self._reference,
                 "element.type": self._type,
@@ -421,12 +436,22 @@ def searchquery(self) -> Any:
         """
         Create a query to find this element.
 
+        MATLAB equivalent: ``ndi.element/searchquery``
+
+        Builds a query matching session_id, element name, type,
+        ndi_element_class, and reference — the same fields used
+        by the MATLAB implementation.
+
         Returns:
             Query matching this element's document
         """
         from ..query import Query
 
-        q = Query("base.id") == self.id
+        q = self._session.searchquery() if self._session is not None else Query("")
+        q = q & (Query("element.name") == self._name)
+        q = q & (Query("element.type") == self._type)
+        q = q & (Query("element.ndi_element_class") == self.ndi_element_class())
+        q = q & (Query("element.reference") == self._reference)
         return q
 
     # =========================================================================

src/ndi/probe/__init__.py

@@ -305,38 +305,24 @@ def getchanneldevinfo(
         }
 
     # =========================================================================
-    # DocumentService Override
+    # Element overrides
     # =========================================================================
 
-    def newdocument(self) -> Any:
-        """
-        Create a new document for this probe.
+    def ndi_element_class(self) -> str:
+        """Return the NDI element class name for document storage.
 
-        Returns:
-            Document representing this probe
-        """
-        from ..document import Document
-
-        doc = Document(
-            "element",
-            **{
-                "element.name": self._name,
-                "element.reference": self._reference,
-                "element.type": self._type,
-                "element.direct": True,  # MATLAB sets direct=1 for probes
-                "base.id": self.id,
-            },
-        )
+        MATLAB equivalent: ``class(ndi_probe_obj)``
 
-        # Set session ID
-        if self._session is not None:
-            doc.set_session_id(self._session.id)
+        Uses the ``probetype2object.json`` mapping to translate the
+        probe *type* (e.g. ``'n-trode'``) to the MATLAB class name
+        (e.g. ``'ndi.probe.timeseries.mfdaq'``).  Falls back to
+        ``'ndi.probe'`` when the type is not in the mapping.
 
-        # Set subject dependency
-        if self._subject_id:
-            doc.set_dependency_value("subject_id", self._subject_id)
-
-        return doc
+        Returns:
+            MATLAB class name string.
+        """
+        type_map = getProbeTypeMap()
+        return type_map.get(self._type, "ndi.probe")
 
     # =========================================================================
     # Static Methods