feat: import Chinese-localized Buzz source snapshot

Signed-off-by: cls_宁波本机 <908705107@qq.com>

mobile/test/features/channels/mentions/mention_ranking_test.dart

@@ -0,0 +1,114 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:buzz/features/channels/mentions/mention_ranking.dart';
+
+// Ported from desktop/src/features/messages/lib/mentionRanking.test.mjs
+// (persona cases omitted — personas are desktop-only).
+
+final channelBrainPubkey = '1' * 64;
+final otherBrainPubkey = '2' * 64;
+
+MentionCandidate candidate({
+  String? displayName = 'Brain',
+  String? secondaryLabel,
+  bool isAgent = false,
+  bool isMember = false,
+  String? pubkey,
+}) {
+  return MentionCandidate(
+    pubkey: pubkey ?? otherBrainPubkey,
+    displayName: displayName,
+    secondaryLabel: secondaryLabel,
+    isAgent: isAgent,
+    isMember: isMember,
+  );
+}
+
+List<String> rankedPubkeys(
+  List<MentionCandidate> candidates, [
+  String query = 'brain',
+]) {
+  return [
+    for (final ranked in rankMentionCandidates(candidates, query))
+      ranked.pubkey,
+  ];
+}
+
+void main() {
+  test('channel members outrank people and other agents', () {
+    final remoteAgent = candidate(isAgent: true, pubkey: otherBrainPubkey);
+    final person = candidate(pubkey: '6' * 64);
+    final channelMember = candidate(
+      isAgent: true,
+      isMember: true,
+      pubkey: channelBrainPubkey,
+    );
+
+    expect(rankedPubkeys([remoteAgent, person, channelMember]), [
+      channelBrainPubkey,
+      '6' * 64,
+      otherBrainPubkey,
+    ]);
+  });
+
+  test('exact and prefix quality sort within the channel-member group', () {
+    final wordPrefixMember = candidate(
+      displayName: 'The Brain',
+      isMember: true,
+      pubkey: '3' * 64,
+    );
+    final exactMember = candidate(
+      displayName: 'Brain',
+      isMember: true,
+      pubkey: channelBrainPubkey,
+    );
+    final prefixMember = candidate(
+      displayName: 'Brainiac',
+      isMember: true,
+      pubkey: '4' * 64,
+    );
+
+    expect(rankedPubkeys([wordPrefixMember, exactMember, prefixMember]), [
+      channelBrainPubkey,
+      '4' * 64,
+      '3' * 64,
+    ]);
+  });
+
+  test('matching secondary labels participate in ranking', () {
+    final memberByHandle = candidate(
+      displayName: 'Acme Bot',
+      secondaryLabel: 'brain@example.com',
+      isMember: true,
+      pubkey: channelBrainPubkey,
+    );
+    final nonMemberName = candidate(
+      displayName: 'Brain',
+      pubkey: otherBrainPubkey,
+    );
+
+    expect(rankedPubkeys([nonMemberName, memberByHandle]), [
+      channelBrainPubkey,
+      otherBrainPubkey,
+    ]);
+  });
+
+  test('non-matching candidates are dropped', () {
+    final match = candidate(displayName: 'Brain', pubkey: channelBrainPubkey);
+    final noMatch = candidate(displayName: 'Pinky', pubkey: '7' * 64);
+
+    expect(rankedPubkeys([match, noMatch]), [channelBrainPubkey]);
+  });
+
+  test('pubkey prefix matches when no label matches', () {
+    final byPubkey = candidate(displayName: 'Pinky', pubkey: 'abc${'0' * 61}');
+
+    expect(rankedPubkeys([byPubkey], 'abc'), ['abc${'0' * 61}']);
+  });
+
+  test('empty query keeps stable order within groups', () {
+    final second = candidate(displayName: 'Beta', pubkey: '9' * 64);
+    final first = candidate(displayName: 'Alpha', pubkey: '8' * 64);
+
+    expect(rankedPubkeys([second, first], ''), ['9' * 64, '8' * 64]);
+  });
+}