Refactor release notes to use MarkdownUI library

- Create MarkdownContentView to encapsulate MarkdownUI rendering
- Replace custom AttributedString markdown parsing with MarkdownUI
- Simplify ReleaseNotesView by removing manual markdown styling
- Improve markdown rendering with proper support for lists, links, and formatting
- Make markdown rendering easily replaceable by keeping it in a dedicated view

readeck/UI/Settings/MarkdownContentView.swift

@@ -0,0 +1,35 @@
+import SwiftUI
+import MarkdownUI
+
+/// A custom view that renders Markdown content using the MarkdownUI library.
+/// This view encapsulates the Markdown rendering logic, making it easy to swap
+/// the underlying Markdown library if needed in the future.
+struct MarkdownContentView: View {
+    let content: String
+
+    var body: some View {
+        Markdown(content)
+            .textSelection(.enabled)
+    }
+}
+
+#Preview {
+    ScrollView {
+        MarkdownContentView(content: """
+# Heading 1
+
+This is a paragraph with **bold** and *italic* text.
+
+## Heading 2
+
+- List item 1
+- List item 2
+- List item 3
+
+### Heading 3
+
+Another paragraph with [a link](https://example.com).
+""")
+        .padding()
+    }
+}

readeck/UI/Settings/ReleaseNotesView.swift

@@ -1,56 +1,14 @@
 import SwiftUI
 
-extension AttributedString {
-    init(styledMarkdown markdownString: String) throws {
-        var output = try AttributedString(
-            markdown: markdownString,
-            options: .init(
-                allowsExtendedAttributes: true,
-                interpretedSyntax: .full,
-                failurePolicy: .returnPartiallyParsedIfPossible
-            ),
-            baseURL: nil
-        )
-
-        for (intentBlock, intentRange) in output.runs[AttributeScopes.FoundationAttributes.PresentationIntentAttribute.self].reversed() {
-            guard let intentBlock = intentBlock else { continue }
-            for intent in intentBlock.components {
-                switch intent.kind {
-                case .header(level: let level):
-                    switch level {
-                    case 1:
-                        output[intentRange].font = .system(.title).bold()
-                    case 2:
-                        output[intentRange].font = .system(.title2).bold()
-                    case 3:
-                        output[intentRange].font = .system(.title3).bold()
-                    default:
-                        break
-                    }
-                default:
-                    break
-                }
-            }
-
-            if intentRange.lowerBound != output.startIndex {
-                output.characters.insert(contentsOf: "\n\n", at: intentRange.lowerBound)
-            }
-        }
-
-        self = output
-    }
-}
-
 struct ReleaseNotesView: View {
     @Environment(\.dismiss) private var dismiss
 
     var body: some View {
         NavigationView {
             ScrollView {
-                VStack(alignment: .leading, spacing: 16) {
-                    if let attributedString = loadReleaseNotes() {
-                        Text(attributedString)
-                            .textSelection(.enabled)
+                VStack(alignment: .leading, spacing: 0) {
+                    if let markdownContent = loadReleaseNotes() {
+                        MarkdownContentView(content: markdownContent)
                             .padding()
                     } else {
                         Text("Unable to load release notes")
@@ -71,13 +29,12 @@ struct ReleaseNotesView: View {
         }
     }
 
-    private func loadReleaseNotes() -> AttributedString? {
+    private func loadReleaseNotes() -> String? {
         guard let url = Bundle.main.url(forResource: "RELEASE_NOTES", withExtension: "md"),
-              let markdownContent = try? String(contentsOf: url),
-              let attributedString = try? AttributedString(styledMarkdown: markdownContent) else {
+              let markdownContent = try? String(contentsOf: url) else {
             return nil
         }
-        return attributedString
+        return markdownContent
     }
 }