Adding OpenHaystack Mobile app

Co-Authored-By: Lukas Burg <lukas.burg@hemalu.de>

openhaystack-mobile/lib/deployment/code_block.dart

@@ -0,0 +1,43 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+class CodeBlock extends StatelessWidget {
+  String text;
+
+  /// Displays a code block that can easily copied by the user.
+  CodeBlock({
+    Key? key,
+    required this.text,
+  }) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8.0),
+      child: Stack(
+        children: [
+          Container(
+            width: double.infinity,
+            constraints: const BoxConstraints(minHeight: 50),
+            decoration: BoxDecoration(
+              borderRadius: const BorderRadius.all(Radius.circular(10)),
+              color: Theme.of(context).colorScheme.background,
+            ),
+            padding: const EdgeInsets.all(5),
+            child: SelectableText(text),
+          ),
+          Positioned(
+            top: 0,
+            right: 5,
+            child: OutlinedButton(
+              child: const Text('Copy'),
+              onPressed: () {
+                Clipboard.setData(ClipboardData(text: text));
+              },
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}