chore(backend): standardize multiline formatting across modules

Reformatted multiline function calls, object definitions, and queries for improved code readability and consistency. Adjusted imports and constraints where necessary.

backend/app/schemas/events.py

@@ -205,9 +205,7 @@ class SprintCompletedPayload(BaseModel):
     sprint_id: UUID = Field(..., description="Sprint ID")
     sprint_name: str = Field(..., description="Sprint name")
     completed_issues: int = Field(default=0, description="Number of completed issues")
-    incomplete_issues: int = Field(
-        default=0, description="Number of incomplete issues"
-    )
+    incomplete_issues: int = Field(default=0, description="Number of incomplete issues")
 
 
 class ApprovalRequestedPayload(BaseModel):