Python: Begin docs for model

This requires use of the pdoc API to work around an issue with the base methods not showing up in the docs.

api/python/build_docs.py

@@ -0,0 +1,21 @@
+# Copyright © SixtyFPS GmbH <info@slint.dev>
+# SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
+
+import slint
+import pdoc
+import os
+
+if __name__ == "__main__":
+    doc = pdoc.doc.Module(slint)
+
+    model_cls = doc.get("Model")
+    for method in model_cls.inherited_members[("builtins", "PyModelBase")]:
+        method.is_inherited = False
+        if not method.name.startswith("_") and method.name != "init_self":
+            model_cls.own_members.append(method)
+
+    out = pdoc.render.html_module(module=doc, all_modules={"foo": doc})
+
+    os.makedirs("docs", exist_ok=True)
+    with open("docs/index.html", "w") as f:
+        f.write(out)