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/archive/hash.ts

@@ -0,0 +1,25 @@
+import { createReadStream } from "fs";
+import { createHash } from "crypto";
+import { pipeline } from "stream/promises";
+import { PassThrough } from "stream";
+
+/**
+ * Compute SHA-256 hash of one or more files by streaming them in order.
+ * Memory usage: O(1) — reads in 64KB chunks regardless of total size.
+ * For multipart archives, pass all parts sorted by part number.
+ */
+export async function hashParts(filePaths: string[]): Promise<string> {
+  const hash = createHash("sha256");
+  for (const filePath of filePaths) {
+    await pipeline(
+      createReadStream(filePath),
+      new PassThrough({
+        transform(chunk, _encoding, callback) {
+          hash.update(chunk);
+          callback();
+        },
+      })
+    );
+  }
+  return hash.digest("hex");
+}