Add link to SymbolKit issue

Author: ethan-kusters

Sources/SwiftDocC/Infrastructure/DocumentationContext.swift

@@ -1098,8 +1098,10 @@ public class DocumentationContext: DocumentationContextDataProviderDelegate {
 
                 let moduleInterfaceLanguages: Set<SourceLanguage>
                 if FeatureFlags.current.isExperimentalObjectiveCSupportEnabled {
-                    // Infer the module's interface languages from the interface
-                    // languages of the first symbol in the symbol graph.
+                    // FIXME: Update with new SymbolKit API once available.
+                    // This is a very inefficient way to gather the source languages
+                    // represented in a symbol graph. Adding a dedicated SymbolKit API is tracked
+                    // with SR-15551 and rdar://85982095.
                     moduleInterfaceLanguages = Set(
                         unifiedSymbolGraph.symbols.flatMap(\.value.sourceLanguages)
                     )

Sources/SwiftDocC/Infrastructure/Symbol Graph/SymbolReference.swift

@@ -151,7 +151,9 @@ private extension Array where Element == String {
 
 extension UnifiedSymbolGraph.Symbol {
     var sourceLanguages: Set<SourceLanguage> {
-        // FIXME: create a SymbolKit API to get all the languages of the symbol
+        // FIXME: Replace with new SymbolKit API once available.
+        // Adding a dedicated SymbolKit API for this purpose is tracked
+        // with SR-15551 and rdar://85982095.
         return Set(
             pathComponents.keys.compactMap { selector in
                 return SourceLanguage(knownLanguageIdentifier: selector.interfaceLanguage)