nzbget, qbittorrent: full nox downloader modules (ADR 0044/0046)

nzbget (usenet, JSON-RPC) and qbittorrent (torrents, WebUI API with manual SID
session). Tools: status, queue/torrents, add, pause/resume, delete. Both poll
and emit module.<app>.download.added and module.<app>.download.completed — the
key plex consumes to rescan; completion is keyed off real success (nzbget
history SUCCESS, qbittorrent progress reaching 1), not mere queue disappearance,
so a failed or deleted item is not reported as done. Typecheck; manifests parse.

modules/nzbget/index.ts

@@ -0,0 +1,64 @@
+// nzbget's events. The tool runtime imports this once the broker is bound. It watches the download
+// queue and the history and turns their comings and goings into mesh events.
+//
+// Emits (novox/hq ADR 0046/0047):
+//   module.nzbget.download.added       — an NZB entered the queue
+//   module.nzbget.download.completed   — an NZB finished successfully (left the queue, landed in
+//                                        history as SUCCESS). This exact routing key is what the
+//                                        plex module consumes (module.*.download.completed) to
+//                                        rescan, so the new file becomes a visible item.
+// Consumes: none.
+//
+// Two diffs, each primed silently on the first look (like plex's and sonarr's index.ts) so a
+// restart mid-download does not re-announce everything already in flight or already finished. The
+// queue tells us what was grabbed; history — not the queue's disappearance — tells us what actually
+// succeeded, since a failed or deleted download also leaves the queue.
+
+import { emit } from "@novox/mesh-sdk/events";
+import { NzbgetClient } from "./client.js";
+
+const nzbget = NzbgetClient.fromEnv();
+
+const inQueue = new Set<number>();
+let queuePrimed = false;
+async function pollQueue(): Promise<void> {
+  const items = await nzbget.getQueue();
+  const now = new Set(items.map((i) => i.id));
+  if (queuePrimed) {
+    for (const item of items) {
+      if (!inQueue.has(item.id)) {
+        await emit("module.nzbget.download.added", { name: item.name, category: item.category, sizeMB: item.sizeMB });
+      }
+    }
+  }
+  inQueue.clear();
+  for (const id of now) inQueue.add(id);
+  queuePrimed = true;
+}
+
+const seenHistory = new Set<number>();
+let historyPrimed = false;
+async function pollHistory(): Promise<void> {
+  const items = await nzbget.getHistory(50);
+  for (const item of items) {
+    if (!seenHistory.has(item.id)) {
+      // A newly-appeared history entry is a completion only if it actually succeeded; a failure or
+      // a manual delete lands in history too, and neither is a "download.completed".
+      if (historyPrimed && item.success) {
+        await emit("module.nzbget.download.completed", { name: item.name, category: item.category, sizeMB: item.sizeMB });
+      }
+      seenHistory.add(item.id);
+    }
+  }
+  historyPrimed = true;
+}
+
+const tick = (fn: () => Promise<void>, everyMs: number): void => {
+  const run = (): void => void fn().catch((err) => console.error(`[nzbget] ${err}`));
+  setInterval(run, everyMs);
+  run();
+};
+tick(pollQueue, 20_000);
+tick(pollHistory, 30_000);
+
+console.log("[nzbget] watching the queue and history, emitting adds and completions");