separate cli and gui application in own python packages. provide database schema as python package.

python/kontor-schema/kontor_schema/base.py

@@ -0,0 +1,20 @@
+import uuid
+from datetime import datetime
+
+from sqlalchemy import Integer, func, String
+from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+class BaseMixin:
+    # id = Column(String, primary_key=True)
+    id: Mapped[str] = mapped_column(primary_key=True, default=uuid.uuid4())
+    # created_date = Column(DateTime)
+    created_date: Mapped[datetime] = mapped_column(default=func.now())
+    # last_modified_date = Column(DateTime)
+    last_modified_date: Mapped[datetime] = mapped_column(default=func.now())
+    # version = Column(Integer)
+    version: Mapped[int] = mapped_column(default=0)