Inspector v2: Add Effect Layers to Scene Explorer

[ryantrem]

Adds effect layers to scene explorer:

• Add uniqueId to EffectLayer
• Add observables for add/remove effect layers, and move the add/remove functions from effectLayerSceneComponent.ts to scene.ts. This seems to be a weird case unlike any other entity types where the actual array of EffectLayers lives in scene.ts, but the functions for adding/removing live in effectLayerSceneComponent.ts and the EffectLayer constructor directly pushes the instance into the scene.effectLayers array. To try to make things consistent, I've moved the addEffectLayer and removeEffectLayer to scene.ts, and call those functions from the EffectLayer constructor and dispose function. @sebavan
• Add the effect layer explorer.

[bjsplat]

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[bjsplat]

Snapshot stored with reference name:
refs/pull/16877/merge

Test environment:
https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/16877/merge/index.html

To test a playground add it to the URL, for example:

https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/16877/merge/index.html#WGZLGJ#4600

Links to test babylon tools with this snapshot:

https://playground.babylonjs.com/?snapshot=refs/pull/16877/merge
https://sandbox.babylonjs.com/?snapshot=refs/pull/16877/merge
https://gui.babylonjs.com/?snapshot=refs/pull/16877/merge
https://nme.babylonjs.com/?snapshot=refs/pull/16877/merge

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https://playground.babylonjs.com/?snapshot=refs/pull/16877/merge#BCU1XR#0

[bjsplat]

You have made possible changes to the playground.
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https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/PLAYGROUND/refs/pull/16877/merge/?snapshot=refs/pull/16877/merge

Note that neither Babylon scenes nor textures are uploaded to the snapshot directory, so some playgrounds won't work correctly.

[bjsplat]

Building or testing the sandbox has failed.

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[bjsplat]

Visualization tests for WebGPU

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[bjsplat]

You have changed file(s) that made possible changes to the sandbox.
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[bjsplat]

WebGL2 visualization test reporter:

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