fix(video): capture pipeline audio before batch script hooks

The audio waveform rides as an attribute on the decoded sample list, but
the batch script hooks rewrap samples into a plain list before the
capture ran, so joint audio-video models muxed silent files whenever a
script runner was attached. Capture the attribute before the hooks run.

modules/processing.py

@@ -513,6 +513,8 @@ def process_images_inner(p: StableDiffusionProcessing) -> Processed:
                 if not _keep:
                     break
 
+            audio = getattr(samples, 'audio', None) # captured before the batch script hooks, which rewrap samples into a plain list without the attribute
+
             if p.scripts is not None and isinstance(p.scripts, scripts_manager.ScriptRunner):
                 p.scripts.postprocess_batch(p, samples, batch_number=n)
             if p.scripts is not None and isinstance(p.scripts, scripts_manager.ScriptRunner):
@@ -531,8 +533,6 @@ def process_images_inner(p: StableDiffusionProcessing) -> Processed:
                         output_images.append(batch_image)
                         infotexts.append(batch_infotext)
 
-            audio = getattr(samples, 'audio', None)
-
             if shared.cmd_opts.lowvram:
                 devices.torch_gc(force=True, reason='lowvram')
             timer.process.record('post')