Fix checksum field not sending values

[noirbizarre]

This PR fix checksum field not exporting values to the form (missing field for checksum.type and wrong name for checksum.value)

[vinyll]

Seems good with me.
However I'm never sure how a widget would react when using the usual keyboard keys (ie: up/down for combo box and enter for selecting) in form with <a @click=… in Vue.

[noirbizarre]

This is not Vue.js specific (the syntax is only a shortcut on raw event handlers). Focus+Enter, Focus+space, touch event should trigger a click event on any natively clickable element (anchor, button...) (with the exception of implicite submission, ie. Enter in focused form submit even if the focus is a radio button).
But you're right, in case of an anchor, I need to check but I might need to leave the href attribute, even if empty, to make the anchor a clickable element. If so, I think I will be able to remove the cursor: pointer; CSS rule 👍

[noirbizarre]

After testing, the type picker does not works on keyboard without the href. Fixed