Add DocC availability information to all directive pages (#704)

* Add in-source DocC availability info to directives

rdar://110036742

* Correct two directive introduced versions

Author: d-ronnqvist

Sources/SwiftDocC/Semantics/Comment.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2021 Apple Inc. and the Swift project authors
+ Copyright (c) 2021-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -18,6 +18,7 @@ import Markdown
  */
 public final class Comment: Semantic, DirectiveConvertible {
     public static let directiveName = "Comment"
+    public static let introducedVersion = "5.5"
     public let originalMarkup: BlockDirective
 
     /// The comment content.

Sources/SwiftDocC/Semantics/ContentAndMedia.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2021 Apple Inc. and the Swift project authors
+ Copyright (c) 2021-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -14,7 +14,7 @@ import Markdown
 /// A piece of media, such as an image or video, with an attached description.
 public final class ContentAndMedia: Semantic, DirectiveConvertible {
     public static let directiveName = "ContentAndMedia"
-    
+    public static let introducedVersion = "5.5"
     public let originalMarkup: BlockDirective
 
     /// The title of this slide.

Sources/SwiftDocC/Semantics/DirectiveConvertable.swift

@@ -20,6 +20,11 @@ public protocol DirectiveConvertible {
      */
     static var directiveName: String { get }
 
+    /**
+     The earliest release of Swift-DocC that supports this directive.
+     */
+    static var introducedVersion: String { get }
+    
     /**
      The `BlockDirective` that was analyzed and converted to this ``Semantic`` object.
      */

Sources/SwiftDocC/Semantics/DirectiveInfrastructure/DirectiveMirror.swift

@@ -227,6 +227,9 @@ extension DirectiveMirror {
         var name: String {
             return type.directiveName
         }
+        var introducedVersion: String {
+            return type.introducedVersion
+        }
 
         let arguments: [ReflectedArgument]
 

Sources/SwiftDocC/Semantics/Intro.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2021 Apple Inc. and the Swift project authors
+ Copyright (c) 2021-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -15,6 +15,7 @@ import Markdown
  An introductory section for instructional pages.
  */
 public final class Intro: Semantic, AutomaticDirectiveConvertible {
+    public static let introducedVersion = "5.5"
     public let originalMarkup: BlockDirective
 
     /// The title of the containing ``Tutorial``.

Sources/SwiftDocC/Semantics/Media/ImageMedia.swift

@@ -14,7 +14,7 @@ import Markdown
 /// A block filled with an image.
 public final class ImageMedia: Semantic, Media, AutomaticDirectiveConvertible {
     public static let directiveName = "Image"
-    
+    public static let introducedVersion = "5.5"
     public let originalMarkup: BlockDirective
 
     @DirectiveArgumentWrapped(

Sources/SwiftDocC/Semantics/Media/VideoMedia.swift

@@ -15,6 +15,8 @@ import Markdown
 public final class VideoMedia: Semantic, Media, AutomaticDirectiveConvertible {
     public static let directiveName = "Video"
 
+    public static let introducedVersion = "5.5"
+    
     public let originalMarkup: BlockDirective
 
     @DirectiveArgumentWrapped(

Sources/SwiftDocC/Semantics/Metadata/Availability.swift

@@ -44,7 +44,8 @@ extension Metadata {
     /// }
     /// ```
     public final class Availability: Semantic, AutomaticDirectiveConvertible {
-        static public let directiveName: String = "Available"
+        public static let directiveName: String = "Available"
+        public static let introducedVersion = "5.8"
 
         public enum Platform: RawRepresentable, Hashable, DirectiveArgumentValueConvertible {
             // FIXME: re-add `case any = "*"` when `isBeta` and `isDeprecated` are implemented

Sources/SwiftDocC/Semantics/Metadata/CallToAction.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2022 Apple Inc. and the Swift project authors
+ Copyright (c) 2022-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -42,6 +42,8 @@ import Markdown
 /// }
 /// ```
 public final class CallToAction: Semantic, AutomaticDirectiveConvertible {
+    public static let introducedVersion = "5.8"
+    
     /// The kind of action the link is referencing.
     public enum Purpose: String, CaseIterable, DirectiveArgumentValueConvertible {
         /// References a link to download an associated asset, like a sample project.

Sources/SwiftDocC/Semantics/Metadata/CustomMetadata.swift

@@ -1,7 +1,7 @@
 /*
  This source file is part of the Swift.org open source project
 
- Copyright (c) 2022 Apple Inc. and the Swift project authors
+ Copyright (c) 2022-2023 Apple Inc. and the Swift project authors
  Licensed under Apache License v2.0 with Runtime Library Exception
 
  See https://swift.org/LICENSE.txt for license information
@@ -11,7 +11,7 @@
 import Foundation
 import Markdown
 
-/// A directive that accepts an arbitary key/valye pair and emits it into the metadata of the page
+/// A directive that accepts an arbitrary key/value pair and emits it into the metadata of the page
 ///
 /// It accepts following parameters:
 ///
@@ -25,6 +25,7 @@ import Markdown
 /// }
 /// ```
 public final class CustomMetadata: Semantic, AutomaticDirectiveConvertible {
+    public static let introducedVersion = "5.8"
     public let originalMarkup: BlockDirective
 
     /// A key to identify a piece of metadata