fix: make appdebug case-insensitive

when commands like `appdebug verbose` are used rather than `appdebug 2`, the command would fail because Verbose != verbose. The enum conversion is now case-insensitive.

src/PepperDash.Core/Logging/Debug.cs

@@ -376,7 +376,7 @@ namespace PepperDash.Core
                     return;
                 }
 
-                if (Enum.TryParse<LogEventLevel>(levelString, out var levelEnum))
+                if (Enum.TryParse<LogEventLevel>(levelString, true, out var levelEnum))
                 {
                     SetDebugLevel(levelEnum);
                     return;