adding static connection

app/schemas/static_connection.py

@@ -0,0 +1,20 @@
+from pydantic import BaseModel, ConfigDict
+
+
+class StaticConnectionBase(BaseModel):
+    od_mm: float
+    od_in: float
+
+
+class StaticConnectionCreate(StaticConnectionBase):
+    pass
+
+
+class StaticConnectionUpdate(BaseModel):
+    od_mm: float | None = None
+    od_in: float | None = None
+
+
+class StaticConnectionRead(StaticConnectionBase):
+    model_config = ConfigDict(from_attributes=True)
+    id: int