style(backend): apply dotnet format whitespace normalization

- Applied dotnet format to 24 files in backend/
- Corrects spacing, indentation, and formatting consistency
- No functional changes to code logic

Ultraworked with Sisyphus <https://github.com/code-yeongyu/oh-my-opencode>
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

backend/WorkClub.Application/Class1.cs

@@ -1,4 +1,4 @@
-namespace WorkClub.Application;
+namespace WorkClub.Application;
 
 public class Class1
 {

backend/WorkClub.Infrastructure/Class1.cs

@@ -1,4 +1,4 @@
-namespace WorkClub.Infrastructure;
+namespace WorkClub.Infrastructure;
 
 public class Class1
 {

backend/WorkClub.Infrastructure/Data/Interceptors/SaveChangesTenantInterceptor.cs

@@ -39,7 +39,8 @@ public class SaveChangesTenantInterceptor : SaveChangesInterceptor
 
     private void SetTenantIdForNewEntities(DbContext? context)
     {
-        if (context == null) return;
+        if (context == null)
+            return;
 
         var tenantId = _tenantAccessor.MultiTenantContext?.TenantInfo?.Identifier;
 

backend/WorkClub.Infrastructure/Migrations/20260303132952_InitialCreate.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using Microsoft.EntityFrameworkCore.Migrations;
 
 #nullable disable

backend/WorkClub.Tests.Integration/UnitTest1.cs

@@ -1,4 +1,4 @@
-namespace WorkClub.Tests.Integration;
+namespace WorkClub.Tests.Integration;
 
 public class UnitTest1
 {