feat(org): user and PM management - list/define users, roles, project assignment (API + organization panel)

backend/app/schemas/procurement.py

@@ -188,8 +188,31 @@ class PMReceiptCreate(APIModel):
     quality_note: str | None = None
 
 
+class UserCreate(APIModel):
+    """Define a new user from the Organization panel (admin / procurement manager).
+
+    casdoor_id is optional: real Casdoor users auto-provision on their first
+    login; a manual entry gets a synthetic casdoor_id so the row can exist
+    before the person ever signs in.
+    """
+
+    first_name: str = Field(min_length=1)
+    last_name: str = ""
+    phone: str | None = None
+    casdoor_id: str | None = None
+    role: Literal["pm", "procurement_manager", "admin"] | None = None
+
+
 class UserRoleUpdate(APIModel):
-    role: Literal["pm", "procurement_manager", "admin"]
+    """role=None revokes the role (and any project assignment)."""
+
+    role: Literal["pm", "procurement_manager", "admin"] | None = None
+
+
+class UserProjectUpdate(APIModel):
+    """Assign/unassign the user's single project (project_id=None unassigns)."""
+
+    project_id: UUID | None = None
 
 
 class RejectQuoteIn(APIModel):