[Remote rendering 4.5] Remote camera interaction end-to-end

### 📝 Description of the feature

Make rotate, pan, and zoom work against the server-side interactor: the client forwards the interaction event, the server applies it to the camera, renders, and streams the updated frame back. The stock interaction adapter doesn't reliably handle the event format the canvas emits, so a direct dispatch stands in.

Note:

In the spike, the stock vtkRemoteInteractionAdapter.ProcessEvent didn't recognize the JSON event format RemoteCanvas emits, because RemoteCanvas was emitting different event shapes (e.g. both flat {x, y} and nested {position: {x, y}} shapes.
A workaround was used in the spike, dispatching events directly to an interactor instead of going through the adapter, since it wasn't clear whether the adapter's strict behavior is intended or an upstream issue whose fix is to accept both shapes.
If a similar issue is encountered in the course of this user story, we could first check with Kitware on whether we resolve the issue by conforming RemoteCanvas to a single shape or whether the fix is on the adapter side (if it's not intended to be as strict)

### Acceptance Criteria

Rotate, pan, and zoom work in remote mode.

### 💵 Business Value

_No response_

### 🔗 Useful links and references

_No response_

首先追蹤 RemoteCanvas 的事件發出流程和伺服器端的 interactor 路徑，然後檢查 vtkRemoteInteractionAdapter.ProcessEvent 以及這裡描述的不同 JSON 事件結構。確認預期的事件格式或直接 dispatch 方案；當旋轉、平移和縮放在遠端模式下正常運作，且更新後的影格被串流傳回時，即表示完成。

由索引模型根據 Issue 內容生成。