feat: [Remote rendering 3.3d] sync camera to server on orientation widget

[LKasianAnsys]

Issue

Resolves #21

Context

This is the last PR of 4 to move ownership of widget state from the client to the server.

Camera sync-back reports the settled browser camera to the server through the sync_camera trigger, and the server drops any report whose origin is not gesture. CameraGestureTracker sets that origin: a camera change counts as a user input only when it follows a mouse drag, a wheel event, or a z / r keydown. Everything else is programmatic, which is what stops a server-pushed camera from echoing back.

Problem: clicking an orientation cube face moved the camera, but the report arrived as programmatic and was dropped. The widget animates the camera inside wasm, outside the input the tracker watched.

Change:

• WasmRenderer observes the widget's EndInteractionEvent and calls CameraGestureTracker.noteWidgetGesture(), which opens the same 300ms input window as a wheel event or a z/r keydown.
• Client-side only; the report still goes through sync_camera.

Requires a VTK upgrade to 9.7.0

This PR should be merged after VTK is bumped to 9.7.0, in #146.

On VTK 9.6.1 (current), proxying the widget to observe it breaks add_dataset: the client allocates ids that collide with the next dataset's, so the new dataset does not render until a reload. This was encountered previously in VISOR, and resulted in a fix, available in 9.7.0.

• Kitware issue: #86
• Upstream fix: VTK MR

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Copilot summary

This pull request adds support for attributing camera moves triggered by the orientation widget as user gestures, ensuring these actions are recognized and sent to the server rather than being dropped as programmatic moves. This is achieved by explicitly marking orientation widget interactions and updating the relevant gesture tracking and renderer logic. The changes also include comprehensive tests to verify the new behavior and clarify documentation.

Orientation widget gesture attribution:

• Added a new noteWidgetGesture method to CameraGestureTracker that marks orientation widget interactions as user gestures, reusing the same timing and retroactive logic as other input types.
• Exposed a passthrough method noteWidgetGesture in VtkScene so that the renderer can trigger gesture marking from widget events.
• In WasmRenderer, registered an observer on the orientation widget's EndInteractionEvent to call noteWidgetGesture, ensuring face clicks are correctly attributed to the user.

Testing updates:

• Added and updated tests to verify that orientation widget interactions are observed, correctly mark gestures, and do not trigger unintended reports. [1] [2] [3] [4] [5]