feat: payload для /start в ботах.

lib/core/cache/info_cache.dart

@@ -3,6 +3,7 @@ import 'dart:async';
 import 'package:flutter/foundation.dart';
 
 import '../../backend/api.dart';
+import '../../models/bot_info.dart';
 import '../../models/chat_info.dart';
 import '../../models/contact_info.dart';
 import '../protocol/opcode_map.dart';
@@ -279,6 +280,36 @@ class PresenceFetch {
   }
 }
 
+class BotInfoFetch {
+  static final _cache = InfoCache<BotInfo>(
+    ttl: const Duration(minutes: 30),
+    fetcher: _fetch,
+  );
+
+  static Future<BotInfo?> get(int botId, {bool forceRefresh = false}) =>
+      _cache.get(botId, forceRefresh: forceRefresh);
+
+  static BotInfo? peek(int botId) => _cache.peek(botId);
+
+  static List<BotCommand> commandsOf(int botId) =>
+      _cache.peek(botId)?.commands ?? const [];
+
+  static void invalidate(int botId) => _cache.invalidate(botId);
+  static void clear() => _cache.clear();
+
+  static Future<BotInfo?> _fetch(int botId) async {
+    final api = _api;
+    if (api == null || api.state != SessionState.online) return null;
+    final resp = await api.sendRequest(Opcode.botInfo, {'botId': botId});
+    final data = resp.payload;
+    if (data is! Map) return null;
+    final info = BotInfo.fromPayload(botId, Map<String, dynamic>.from(data));
+    final contact = info.contact;
+    if (contact != null) ContactInfoFetch.putContact(botId, contact.raw);
+    return info;
+  }
+}
+
 class ChatInfoFetch {
   static final _cache = InfoCache<ChatInfo>(
     ttl: const Duration(minutes: 5),

lib/core/links/max_link.dart

@@ -3,8 +3,11 @@ enum MaxLinkKind { call, invite, user, content, public, auth, stickerSet }
 class MaxLink {
   final MaxLinkKind kind;
   final String url;
+  final String baseUrl;
+  final String? startPayload;
 
-  const MaxLink(this.kind, this.url);
+  const MaxLink(this.kind, this.url, {String? baseUrl, this.startPayload})
+    : baseUrl = baseUrl ?? url;
 
   static final RegExp _host = RegExp(
     r'^https?://(?:www\.)?max\.ru/(.+)$',
@@ -33,7 +36,8 @@ class MaxLink {
     final match = _host.firstMatch(url);
     if (match == null) return null;
 
-    final path = match.group(1)!.split('?').first.split('#').first;
+    final rest = match.group(1)!;
+    final path = rest.split('?').first.split('#').first;
     final segments = path
         .split('/')
         .where((s) => s.isNotEmpty)
@@ -59,6 +63,18 @@ class MaxLink {
 
     if (_reserved.contains(segments.first.toLowerCase())) return null;
     if (!_segment.hasMatch(segments.first)) return null;
-    return MaxLink(MaxLinkKind.public, url);
+    return MaxLink(
+      MaxLinkKind.public,
+      url,
+      baseUrl: 'https://max.ru/${segments.join('/')}',
+      startPayload: _startPayload(rest),
+    );
+  }
+
+  static String? _startPayload(String rest) {
+    final parts = rest.split('#').first.split('?');
+    if (parts.length < 2) return null;
+    final value = Uri.splitQueryString(parts[1])['start']?.trim();
+    return (value == null || value.isEmpty) ? null : value;
   }
 }