Tighten YuE lyrics validation and Comfy music workflow wiring.

Require section tags before queueing YuE and keep the ACE/YuE path changes that were already in progress.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/utils/musicChain.ts

@@ -1,5 +1,5 @@
 import { createJob, emitJob, type Job } from '~/server/utils/jobs'
-import { extractAudio, fetchHistory, fetchHistoryAll, findHistoryAudio, purgeComfyArtifacts, queuePrompt } from '~/server/utils/comfy'
+import { extractAudio, fetchHistory, fetchHistoryAll, findHistoryAudio, freeComfyVram, purgeComfyArtifacts, queuePrompt } from '~/server/utils/comfy'
 import { comfyWsUrl } from '~/server/utils/comfy'
 import { ensureComfyReady } from '~/server/utils/comfyLifecycle'
 import { downloadComfyAudio, saveTrack } from '~/server/utils/library'
@@ -33,7 +33,7 @@ function sleep(ms: number) {
 function classifyError(message: string) {
   const lower = message.toLowerCase()
   if (lower.includes('out of memory') || lower.includes('exceed allowed memory') || (lower.includes('cuda') && lower.includes('alloc')) || lower.includes('vram')) {
-    return 'ComfyUI ran out of VRAM. For YuE use shorter lyrics (fewer sections) or ACE-Step instead.'
+    return 'ComfyUI ran out of VRAM on YuE. Sleep→Poke Comfy, don’t run video/image first, use one short [Chorus] only — or use ACE-Step.'
   }
   if (lower.includes('econnrefused') || lower.includes('unreachable') || lower.includes('fetch failed')) {
     return 'ComfyUI host connection dropped. Confirm the desktop instance is running.'
@@ -372,6 +372,10 @@ export async function startMusicJob(params: MusicJobParams) {
       emitJob(job, { type: 'status', message: `Queueing ${engineLabel}...`, progress: 6 })
       await waitForSocket(job, 4000)
       await assertMusicEngineNodes(params.engine)
+      if (params.engine === 'yue') {
+        emitJob(job, { type: 'status', message: 'Freeing Comfy VRAM for YuE…', progress: 5 })
+        await freeComfyVram()
+      }
       const graph = buildMusicWorkflow({
         tags: params.tags,
         lyrics: params.instrumental ? '' : params.lyrics,