add warning for dart dSYM support

Author: smeubank

docs/platforms/dart/common/debug-symbols/index.mdx

@@ -6,6 +6,12 @@ sidebar_order: 3
 
 Debug symbols are essential for understanding stack traces in your Dart application when errors occur. Without debug symbols, stack traces from minified or obfuscated code can be difficult or impossible to interpret.
 
+<Alert level="warning">
+
+Sentry currently doesn't support uploading debug symbols for pure Dart applications. Please see the [Flutter debug symbols documentation](/platforms/dart/guides/flutter/debug-symbols/) for Flutter applications. This feature is being tracked in our GitHub Issue: [sentry-dart/#1508](https://github.com/getsentry/sentry-dart/issues/1508).
+
+</Alert>
+
 ## What Are Debug Symbols?
 
 Debug symbols provide the necessary information to convert program addresses back to function names, source file names, and line numbers. When you build a Dart application, especially with obfuscation or optimization enabled, this information is typically removed from the main application bundle to reduce size.