feat: MeshCore SAR - Flutter BLE mesh radio companion app

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/utils/key_comparison.dart

@@ -0,0 +1,18 @@
+import 'dart:typed_data';
+
+/// Extension on Uint8List to provide comparison functionality for public keys.
+///
+/// This extension is used to compare MeshCore public keys (32 bytes) or their
+/// prefixes (6 bytes) across the application.
+extension Uint8ListComparison on Uint8List {
+  /// Compares this Uint8List with another for exact equality.
+  ///
+  /// Returns true if both lists have the same length and identical bytes.
+  bool matches(Uint8List other) {
+    if (length != other.length) return false;
+    for (int i = 0; i < length; i++) {
+      if (this[i] != other[i]) return false;
+    }
+    return true;
+  }
+}