feat: add share calendar API

backend/src/v1/schedule_items/schemas.py

@@ -96,3 +96,24 @@ class ScheduleItemListItem(BaseModel):
 class ScheduleItemListRequest(BaseModel):
     start_at: datetime
     end_at: datetime
+
+
+class ScheduleItemShareRequest(BaseModel):
+    email: str = Field(..., description="Email of user to share with")
+    permission_view: bool = Field(True, description="Grant view permission")
+    permission_edit: bool = Field(False, description="Grant edit permission")
+    permission_invite: bool = Field(False, description="Grant invite permission")
+
+    def _permission_value(self) -> int:
+        value = 0
+        if self.permission_view:
+            value |= 1
+        if self.permission_edit:
+            value |= 4
+        if self.permission_invite:
+            value |= 2
+        return value
+
+
+class ScheduleItemShareResponse(BaseModel):
+    message: str