fix: bug-fix sweep across node, audio, render, plugin subsystems

Node core:
- MathNode/TrigonometryNode combo strings realigned with Operation enums
- mathbase scalar/vector operand pick no longer uses bitwise type checks
- NodeSetPositionAndDependenciesRecursively moves dependencies again
- RemoveAllKeyframes undo actually restores keyframes
- NodeGroup GetInputName null-deref guard, passthrough ids use input id
- NodeValueTable::Has is an exact type match; tag fallback only for
  empty tags; kStrCombo/kPushButton get data type names
- delete_all_keyframes no longer loops forever on unparented keyframes;
  keyframe-load failures propagate; rational interpolation falls back to
  double; OpacityEffect no longer leaks its internal MathNode

Audio/footage:
- AudioVisualWaveform: GetSummaryFromTime underflow OOB read, TrimIn
  prepend length bookkeeping, OverwriteSums source channel indexing
- PanNode inserts the pan value into the sample job (keyframed pan
  works); OutputParamsChanged is emitted on device change; PortAudio
  device indices are validated before Pa_GetDeviceInfo
- Footage: AdjustTimeByLoopMode no longer hangs/UBs on degenerate
  lengths, GetStreamIndex bounds-checked, CheckFootage clears stale
  state on missing files, failed probes are not cached,
  FootageDescription::Load requires its own root element

Render/track:
- ViewerOutput pushes the tagged samples value; TrackList disconnects
  the track-height lambda; GetTrackFromReference validity check
- RenderManager dummy backend: null-initialized threads, guarded
  decoder-cache/timer paths; Renderer::Destroy releases color cache
  shaders/textures; unknown dynamic backends no longer alias to oakgl
- SharedMemoryRegion POSIX attach validates segment size; ReadMessage
  skips blank lines instead of failing; GC counter clamped;
  IsRenderingCustomRange implemented; TimeOffsetNode gets a true
  inverse OutputTimeAdjustment; zero-speed clips return the held frame

Plugin/nodes:
- OliveClip: stored default region of definition is honored, on-demand
  images are cached; OliveHost sets host identity properties and logs
  instead of showing modal dialogs offscreen; Plugin.h dead decls gone
- DespillNode guards graph-less use with Rec.709 fallback; description
  typos fixed (despill, swirl); mosaic applies when only one axis
  matches; Windows-only Project filename separator test fixed

app/pluginSupport/OliveClip.cpp

@@ -467,7 +467,14 @@ olive::plugin::OliveClipInstance::getImage(OfxTime time,
 			return nullptr;
 		}
 
+		// Cache the on-demand image like the output path does, so repeated
+		// fetches at the same time reuse it and getConnected() reflects it.
+		// The extra reference keeps the cached image alive when the plugin
+		// releases its own.
+		pruneImagesCache();
 		Image *image = new Image(*this, preferred_params, bounds, rod, true);
+		images_.insert(time, image);
+		image->addReference();
 		return image;
 	}
 }
@@ -546,6 +553,11 @@ olive::plugin::OliveClipInstance::getRegionOfDefinition(OfxTime time) const
 	double par = params_.pixel_aspect_ratio().toDouble();
 	regionOfDefinition.x2 = params_.width() * par;
 	regionOfDefinition.y2 = params_.height();
+	if (regionOfDefinition.x2 <= 0 || regionOfDefinition.y2 <= 0) {
+		// The params provide no usable region; fall back to the default set
+		// via setDefaultRegionOfDefinition().
+		return defaultRegionOfDefinitions_;
+	}
 	return regionOfDefinition;
 }
 void olive::plugin::OliveClipInstance::setRegionOfDefinition(