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.

SECURITY.md

@@ -1,24 +1,24 @@
-# Security Policy
-
-## Reporting a vulnerability
-
-If you believe you’ve found a security vulnerability in EchoHub (for example: auth bypass, token leakage, file upload validation bypass, RCE, etc.), please **do not** open a public GitHub issue.
-
-Preferred: use GitHub’s private vulnerability reporting ("Report a vulnerability"):
-
-- https://github.com/HueByte/EchoHub/security/advisories/new
-
-If that link is unavailable for your account, contact the maintainer via GitHub:
-
-- https://github.com/HueByte
-
-## What to include
-
-- A clear description of the issue and potential impact
-- Reproduction steps or a proof-of-concept
-- Affected versions / commit SHA
-- Any relevant logs (with secrets removed)
-
-## Disclosure
-
-I’ll acknowledge receipt, investigate, and work on a fix. Please avoid publicly disclosing details until a fix is available.
+# Security Policy
+
+## Reporting a vulnerability
+
+If you believe you’ve found a security vulnerability in EchoHub (for example: auth bypass, token leakage, file upload validation bypass, RCE, etc.), please **do not** open a public GitHub issue.
+
+Preferred: use GitHub’s private vulnerability reporting ("Report a vulnerability"):
+
+- https://github.com/HueByte/EchoHub/security/advisories/new
+
+If that link is unavailable for your account, contact the maintainer via GitHub:
+
+- https://github.com/HueByte
+
+## What to include
+
+- A clear description of the issue and potential impact
+- Reproduction steps or a proof-of-concept
+- Affected versions / commit SHA
+- Any relevant logs (with secrets removed)
+
+## Disclosure
+
+I’ll acknowledge receipt, investigate, and work on a fix. Please avoid publicly disclosing details until a fix is available.