feat: fix channel scanning bugs, add package tags, and kickstarters tab

Bug fixes:
- Fix channels not being scanned by paginating TDLib getChats (was only
  loading first batch, additional channels were unknown to TDLib)
- Add per-channel getChat pre-load as safety net before scanning
- Fix preview pictures not loading by checking previewData instead of
  previewMsgId for hasPreview flag
- Prevent previewMsgId from being set when preview download fails

Package Tags:
- Add tags Text[] column to Package with migration backfilling from
  channel categories
- Worker auto-inherits source channel category as initial tag
- Tag filter dropdown and Tags column in STL Files table
- Server actions for individual and bulk tag editing

Kickstarters Tab:
- New KickstarterHost, Kickstarter, and KickstarterPackage models
- Full CRUD with delivery status, payment status, host management
- Package linking (many-to-many with existing packages)
- Sidebar entry with Gift icon
- Table with search, filters, modal forms

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

worker/src/tdlib/chats.ts

@@ -23,12 +23,11 @@ export async function getAccountChats(
 ): Promise<TelegramChatInfo[]> {
   const chats: TelegramChatInfo[] = [];
 
-  // Load main chat list — TDLib loads in batches
-  let offsetOrder = "9223372036854775807"; // max int64 as string
-  let offsetChatId = 0;
-  let hasMore = true;
-
-  while (hasMore) {
+  // Load ALL chats from the main list by paginating getChats.
+  // TDLib's getChats returns batches — keep calling until it returns
+  // an empty list, which signals all chats have been loaded.
+  const MAX_PAGES = 50; // safety limit (50 × 100 = 5000 chats)
+  for (let page = 0; page < MAX_PAGES; page++) {
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
     const result = (await withFloodWait(
       () => client.invoke({
@@ -95,10 +94,6 @@ export async function getAccountChats(
       }
     }
 
-    // getChats with chatListMain returns all chats at once in newer TDLib versions
-    // So we break after the first batch
-    hasMore = false;
-
     await sleep(config.apiDelayMs);
   }