Creates a new drop zone bound to the given element and file input.
Attaches global dragenter / dragover / dragleave / drop listeners
on document (matching the pattern used in welcome.ts) so the entire
page surface acts as a valid drop target. A click on element delegates
to fileInput.click() to open the system file picker.
The dragCounter tracks nested dragenter/dragleave pairs to avoid
flickering when the pointer moves over child elements.
Creates a new drop zone bound to the given element and file input.
Attaches global
dragenter/dragover/dragleave/droplisteners ondocument(matching the pattern used inwelcome.ts) so the entire page surface acts as a valid drop target. A click onelementdelegates tofileInput.click()to open the system file picker.The
dragCountertracks nesteddragenter/dragleavepairs to avoid flickering when the pointer moves over child elements.