Improve Gizmo API docs

[willeastcott]

Add much more comprehensive docs for the Gizmo API.

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[Copilot]

Pull Request Overview

This PR significantly improves the Gizmo API documentation by adding comprehensive descriptions and usage examples for the TranslateGizmo, ScaleGizmo, and RotateGizmo.

• Enhanced doc comments for TranslateGizmo with detailed description and a clear code example
• Enhanced doc comments for ScaleGizmo including updated examples and API references
• Enhanced doc comments for RotateGizmo with improved descriptive text and usage demonstration

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/extras/gizmo/translate-gizmo.js	Updated documentation and code example for translation gizmo
src/extras/gizmo/scale-gizmo.js	Updated documentation and code example for scaling gizmo
src/extras/gizmo/rotate-gizmo.js	Updated documentation and code example for rotation gizmo

Comments suppressed due to low confidence (3)

src/extras/gizmo/translate-gizmo.js:45

• [nitpick] The example uses 'cameraComponent' while the parameter documentation refers to the camera as 'camera'. Consider making the naming consistent across the API documentation.

* const gizmo = new pc.TranslateGizmo(cameraComponent, gizmoLayer);

src/extras/gizmo/scale-gizmo.js:39

• [nitpick] The example uses 'cameraComponent' in contrast to the parameter description which uses 'camera'. Align the naming to avoid confusion.

* const gizmo = new pc.ScaleGizmo(cameraComponent, gizmoLayer);

src/extras/gizmo/rotate-gizmo.js:45

• [nitpick] The variable 'cameraComponent' in the example should be consistently named in line with the parameter documentation (i.e., 'camera') to maintain uniformity across the API docs.

* const gizmo = new pc.RotateGizmo(cameraComponent, gizmoLayer);