* Add Page Zoom Control
Adds MQTT discovery for a "Page Zoom" input to control the `WEBVIEW.viewZoom` parameter.
The MQTT value has been configured to be in % which is then converted to a scale factor when assigned or read from `WEBVIEW.viewZoom`.
* Correct Type for page_zoom publishConfig
Accidentally replaced "number" with "zoom" when changing paramters.
* Add updateZoom Functionality to webview
Add a setter function for the viewZoom property that updates the zoom factor for all views when the property is changed.
leukipp