feat: export ErrorData from rspack_error crate (#12166)

Add ErrorData to the public exports to allow external access to error data structures.

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Co-authored-by: Claude <noreply@anthropic.com>

Author: ityuany

crates/rspack_error/src/lib.rs

@@ -16,7 +16,7 @@ pub use self::{
   diagnostic::Diagnostic,
   diagnostic_array::{IntoTWithDiagnosticArray, TWithDiagnosticArray},
   displayer::{Display, Renderer, StdioDisplayer, StringDisplayer},
-  error::{Error, Label, Severity},
+  error::{Error, ErrorData, Label, Severity},
 };
 
 pub type Result<T, E = Error> = std::result::Result<T, E>;