Refactor and update various components of EchoHub.Server

- Updated launchSettings.json for consistency.
- Refactored FileValidationHelper to improve image validation logic.
- Enhanced ServerDirectoryService for better connection handling and user count updates.
- Improved DatabaseSetup for legacy database handling and seeding default channels.
- Refined FirstRunSetup to ensure JWT secret generation.
- Removed appsettings.Development.json as it is no longer needed.
- Updated EchoHub.Tests project file for consistency.
- Added unit tests for FileValidationHelper and PresenceTracker with improved assertions.
- Updated ValidationConstantsTests to ensure regex validations are correct.
- Cleaned up solution file formatting for better readability.

src/EchoHub.Core/Models/RefreshToken.cs

@@ -1,17 +1,17 @@
-namespace EchoHub.Core.Models;
-
-public class RefreshToken
-{
-    public Guid Id { get; set; }
-    public required string TokenHash { get; set; }
-    public Guid UserId { get; set; }
-    public DateTimeOffset ExpiresAt { get; set; }
-    public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;
-    public DateTimeOffset? RevokedAt { get; set; }
-
-    public bool IsExpired => DateTimeOffset.UtcNow >= ExpiresAt;
-    public bool IsRevoked => RevokedAt is not null;
-    public bool IsActive => !IsExpired && !IsRevoked;
-
-    public User? User { get; set; }
-}
+namespace EchoHub.Core.Models;
+
+public class RefreshToken
+{
+    public Guid Id { get; set; }
+    public required string TokenHash { get; set; }
+    public Guid UserId { get; set; }
+    public DateTimeOffset ExpiresAt { get; set; }
+    public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;
+    public DateTimeOffset? RevokedAt { get; set; }
+
+    public bool IsExpired => DateTimeOffset.UtcNow >= ExpiresAt;
+    public bool IsRevoked => RevokedAt is not null;
+    public bool IsActive => !IsExpired && !IsRevoked;
+
+    public User? User { get; set; }
+}