MaterialXLoader: "time" and "frame" MaterialX nodes not loaded

[hybridherbst]

Description

Seems the time and frame application nodes from MaterialX are already supported as nodes, but not processed by MaterialXLoader.

Related to #24680

Reproduction steps

1. Load this file with MaterialXLoader: https://github.com/AcademySoftwareFoundation/MaterialX/blob/main/resources/Materials/TestSuite/stdlib/application/time_frame.mtlx
2. It contains two materials, one for "time" and one for "frame"
3. Note that "time" node and "frame" node are not supported

Code

I tried to fix it with

	// << Application >>
	new MXElement( 'time', timerLocal, [ 'timeScale' ] ),
	// new MXElement( 'frame', ... ),

in MaterialXLoader.js, but then I get a shader error, so that doesn't seem to be the right approach. cc @sunag

Live example

Screenshots

No response

Version

r167

Device

No response

Browser

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OS

No response

[hybridherbst]

@sunag would love your input here! Thanks!