Fix: Voice-Auto-Naming tot (TitaNet bricht bei langen Schnitten ab + vergiftete Promise-Kette)

identifySpeakers() embettete den laengsten Lauf ungekuerzt; TitaNet-ONNX bricht
ab 180 s ab (broadcast 12288 by 17998) und riss den spk_embed-Helfer mit. Da
spk.js die Aufrufe ueber eine Promise-Kette serialisiert, schlugen danach ALLE
weiteren Sprecher mit 'spk beendet' fehl.

- ID_CUT_SEC=25s in identifySpeakers
- Kette in spk.js und tdChain in recorder.js failure-isoliert
- pro Name gewinnt nur der beste Kosinus (Fabio war auf 2 Clustern)

app/server.js

@@ -65,18 +65,33 @@ async function identifySpeakers(recData) {
     const len = cur.end - cur.start;
     if (!best[cur.speaker] || len > best[cur.speaker].len) best[cur.speaker] = { start: cur.start, end: cur.end, len };
   }
-  const map = {};
+  // Cut at most ID_CUT_SEC: onnxruntime ABORTS the embedding helper on very long
+  // inputs (reproduced: 180 s -> "Non-zero status code returned while running
+  // Where"; 20/60 s fine). On #74 the longest run of a moderator was minutes
+  // long, which killed the helper on the first speaker and — through the then
+  // poisoned promise chain in spk.js — every speaker after it ("spk beendet"),
+  // i.e. voice auto-naming was dead for the whole recording.
+  const ID_CUT_SEC = 25;
+  const hits = [];
   for (const sp of speakers) {
     const r = best[sp]; if (!r) continue;
     const seg = `/tmp/idseg_${recData.id}_${sp}.wav`;
+    const from = r.start / 1000;
+    const to = Math.min(r.end / 1000, from + ID_CUT_SEC);
     try {
-      await pexec('ffmpeg', ['-y', '-i', wavPath, '-ss', String(r.start / 1000), '-to', String(r.end / 1000), '-ar', '16000', '-ac', '1', seg]);
+      await pexec('ffmpeg', ['-y', '-i', wavPath, '-ss', String(from), '-to', String(to), '-ar', '16000', '-ac', '1', seg]);
       const emb = await spk.embed(seg);
       const m = spk.bestMatch(emb, vps);
-      if (m) map[sp] = m.name;
+      if (m) hits.push({ speaker: sp, name: m.name, score: m.score });
     } catch (e) { console.error('identify', sp, e.message); }
     finally { try { fs.unlinkSync(seg); } catch {} }
   }
+  // One enrolled person can only BE one cluster: keep the best-scoring match per
+  // name (#74 handed "Fabio" to two clusters at once).
+  const bestByName = {};
+  for (const h of hits) if (!bestByName[h.name] || h.score > bestByName[h.name].score) bestByName[h.name] = h;
+  const map = {};
+  for (const h of Object.values(bestByName)) map[h.speaker] = h.name;
   return map;
 }