Make FirebaseAI.GeneratedContent.Kind equatable on iOS 15+

Author: andrewheard

FirebaseAI/Sources/Types/Public/StructuredOutput/GeneratedContent.swift

@@ -208,7 +208,7 @@
     /// The kinds of values that can be represented by generated content.
     ///
     /// **Public Preview**: This API is a public preview and may be subject to change.
-    enum Kind: Sendable {
+    enum Kind: Equatable, Sendable {
       /// A null value.
       case null
       /// A boolean value.
@@ -245,11 +245,6 @@
       }
     }
 
-    @available(iOS 26.0, macOS 26.0, *)
-    @available(tvOS, unavailable)
-    @available(watchOS, unavailable)
-    extension FirebaseAI.GeneratedContent.Kind: Equatable {}
-
     @available(iOS 26.0, macOS 26.0, *)
     @available(tvOS, unavailable)
     @available(watchOS, unavailable)

FirebaseAI/Tests/TestApp/Tests/Integration/GenerativeModelSessionTests.swift

@@ -36,9 +36,7 @@
       let content = response.content
       #expect(!content.isEmpty)
       #expect(response.rawContent.isComplete)
-      if #available(iOS 26.0, macOS 26.0, visionOS 26.0, *) {
-        #expect(response.rawContent.kind == .string(content))
-      }
+      #expect(response.rawContent.kind == .string(content))
       #expect(response.rawContent.generationID != nil)
       #expect(response.rawResponse.text == content)
     }
@@ -258,9 +256,7 @@
       #expect(!content.isEmpty)
       #expect(response.rawContent.isComplete, "The final response was not marked as complete.")
       #expect(response.rawContent.generationID == generationID)
-      if #available(iOS 26.0, macOS 26.0, visionOS 26.0, *) {
-        #expect(response.rawContent.kind == .string(content))
-      }
+      #expect(response.rawContent.kind == .string(content))
       if let text = response.rawResponse.text {
         #expect(content.hasSuffix(text))
       }