Merge branch 'spike/block2-derisking'

apps/app_seeds/lib/services/profile_cache.dart

@@ -0,0 +1,25 @@
+import '../security/secret_store.dart';
+
+/// Remembers the display names peers have published (their NIP-01 kind:0
+/// `name`), so the inbox and chat show a human name instead of a raw key —
+/// even offline. Keystore-backed (no plaintext at rest).
+class ProfileCache {
+  ProfileCache(this._store);
+
+  final SecretStore _store;
+  static const _prefix = 'tane.social.name.';
+
+  /// The cached name for [pubkeyHex], or null if none is known.
+  Future<String?> name(String pubkeyHex) async {
+    final value = await _store.read('$_prefix$pubkeyHex');
+    return (value == null || value.isEmpty) ? null : value;
+  }
+
+  Future<void> setName(String pubkeyHex, String name) =>
+      _store.write('$_prefix$pubkeyHex', name.trim());
+}
+
+/// A compact, human-ish rendering of a public key when no name is known yet.
+String shortPubkey(String pubkeyHex) => pubkeyHex.length <= 12
+    ? pubkeyHex
+    : '${pubkeyHex.substring(0, 6)}…${pubkeyHex.substring(pubkeyHex.length - 4)}';