handleKeydown computed a 'typing' guard for the event target but only
applied it to the drawer-shortcut block (t/s/b/?//). The vi-style page
turns (h/l), arrows, and zoom keys (+/−/0) fired regardless, so typing
into the note textarea hijacked the keys: 'Wh' turned back a page on the
h, arrows moved pages instead of the caret, and digits/minus zoomed.
Return early for INPUT/SELECT/TEXTAREA/contentEditable targets, keeping
Escape live so popovers and drawers stay dismissable from the keyboard
mid-note. Covers the selection-popover note field, the notes drawer
textarea, bookmark rename, and the search box. The now-unreachable
'!typing' condition on the shortcut block is dropped.