fix: use searchChatMessages instead of getChatHistory for channel scanning

getChatHistory fails silently in supergroups with hidden history for new
members, returning only system messages. searchChatMessages with document
and photo filters works regardless of history visibility settings.

Also adds getChats call after TDLib client creation to populate the chat
list, preventing 'Chat not found' errors.

worker/src/worker.ts

@@ -333,6 +333,18 @@ export async function runWorkerForAccount(
       phone: account.phone,
     });
 
+    // Load the chat list so TDLib knows about all chats
+    // Without this, getChat/getChatHistory fail with "Chat not found"
+    try {
+      await client.invoke({
+        _: "getChats",
+        chat_list: { _: "chatListMain" },
+        limit: 1000,
+      });
+    } catch {
+      // Ignore — chat list may already be loaded
+    }
+
     const counters = {
       messagesScanned: 0,
       zipsFound: 0,