Add fullscreen image view

Closes #9

lib/pages/article.dart

@@ -1,4 +1,5 @@
 import 'package:feet/api/api.dart';
+import 'package:feet/pages/image_view.dart';
 import 'package:feet/widgets/homepage_post.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
@@ -112,6 +113,18 @@ class _ArticlePageState extends State<ArticlePage> {
             child: SelectionArea(
               child: Html(
                 data: widget.article.html,
+                onImageTap: (url, ctx, attributes, element) => Navigator.of(context).push(
+                  PageRouteBuilder(
+                    opaque: false,
+                    pageBuilder: (context, _, __) => ImageView(url: url!),
+                    transitionsBuilder: (context, animation, _, child) {
+                      return FadeTransition(
+                        opacity: animation,
+                        child: child,
+                      );
+                    },
+                  ),
+                ),
               ),
             ),
           )

lib/pages/image_view.dart

@@ -0,0 +1,17 @@
+import 'package:flutter/material.dart';
+import 'package:photo_view/photo_view.dart';
+
+class ImageView extends StatelessWidget {
+  final String url;
+  const ImageView({super.key, required this.url});
+
+  @override
+  Widget build(BuildContext context) {
+    return PhotoView(
+      backgroundDecoration: BoxDecoration(color: Theme.of(context).colorScheme.background.withAlpha(200)),
+      maxScale: 5.0,
+      minScale: PhotoViewComputedScale.contained,
+      imageProvider: NetworkImage(url),
+    );
+  }
+}

pubspec.lock

@@ -440,6 +440,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "5.1.0"
+  photo_view:
+    dependency: "direct main"
+    description:
+      name: photo_view
+      sha256: "8036802a00bae2a78fc197af8a158e3e2f7b500561ed23b4c458107685e645bb"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.14.0"
   platform:
     dependency: transitive
     description:

pubspec.yaml

@@ -45,6 +45,7 @@ dependencies:
   workmanager: ^0.5.1
   flutter_local_notifications: ^9.1.4
   permission_handler: ^10.2.0
+  photo_view: ^0.14.0
 
 dev_dependencies:
   flutter_test: