feat: add Telegram integration with forum topic support and creator tracking

Adds full Telegram ZIP ingestion pipeline: TDLib worker service scans source
channels for archive files, deduplicates by content hash, extracts metadata,
uploads to archive channel, and indexes in Postgres. Forum supergroups are
scanned per-topic with topic names used as creator. Filename-based creator
extraction (e.g. "Mammoth Factory - 2026-01.zip") serves as fallback.

Includes admin UI for managing accounts/channels, simplified account setup
(API credentials via env vars), auth code/password submission dialog,
package browser with creator column, and live ingestion activity tracking.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

worker/src/upload/channel.ts

@@ -0,0 +1,76 @@
+import type { Client } from "tdl";
+import { config } from "../util/config.js";
+import { childLogger } from "../util/logger.js";
+
+const log = childLogger("upload");
+
+export interface UploadResult {
+  messageId: bigint;
+}
+
+/**
+ * Upload one or more files to a destination Telegram channel.
+ * For multipart archives, each file is sent as a separate message.
+ * Returns the message ID of the first uploaded message.
+ */
+export async function uploadToChannel(
+  client: Client,
+  chatId: bigint,
+  filePaths: string[],
+  caption?: string
+): Promise<UploadResult> {
+  let firstMessageId: bigint | null = null;
+
+  for (let i = 0; i < filePaths.length; i++) {
+    const filePath = filePaths[i];
+    const fileCaption =
+      i === 0 && caption ? caption : undefined;
+
+    log.debug(
+      { chatId: Number(chatId), filePath, part: i + 1, total: filePaths.length },
+      "Uploading file to channel"
+    );
+
+    const result = (await client.invoke({
+      _: "sendMessage",
+      chat_id: Number(chatId),
+      input_message_content: {
+        _: "inputMessageDocument",
+        document: {
+          _: "inputFileLocal",
+          path: filePath,
+        },
+        caption: fileCaption
+          ? {
+              _: "formattedText",
+              text: fileCaption,
+            }
+          : undefined,
+      },
+    })) as { id: number };
+
+    if (i === 0) {
+      firstMessageId = BigInt(result.id);
+    }
+
+    // Rate limit delay between uploads
+    if (i < filePaths.length - 1) {
+      await sleep(config.apiDelayMs);
+    }
+  }
+
+  if (firstMessageId === null) {
+    throw new Error("Upload failed: no messages sent");
+  }
+
+  log.info(
+    { chatId: Number(chatId), messageId: Number(firstMessageId), files: filePaths.length },
+    "Upload complete"
+  );
+
+  return { messageId: firstMessageId };
+}
+
+function sleep(ms: number): Promise<void> {
+  return new Promise((resolve) => setTimeout(resolve, ms));
+}