Propagate `InputEvents` without position either
- during the Input-stage, when it has focus or
- during the Unhandled-Input-stage, otherwise
This makes sure that Gui-Input happens in the correct order.
Move "Unhandled key Input" handling before "Unhandled Input" handling,
so that Unicode input with Alt / Ctrl modifiers are sent to the nodes
in the correct order.
Change the default focus mode of `SubViewportContainer` from
`FOCUS_NONE` to `FOCUS_CLICK`, to automatically remove focus from
other `Control`-nodes, when clicking inside a `SubViewport`.
We don't use that info for anything, and it generates unnecessary diffs
every time we bump the minor version (and CI failures if we forget to
sync some files from opt-in modules (mono, text_server_fb).
This makes it easier to spot syntax errors when editing the
class reference. The schema is referenced locally so validation
can still work offline.
Each class XML's schema conformance is also checked on GitHub Actions.