The mobile command/tool approval popup rendered too small — options didn't all fit
and required scrolling within the cramped popup to select (Android WebUI wrapper).
Raises the mobile @supports(dvh) .approval-inner max-height cap from
min(52dvh,360px) to min(60dvh,420px) so the options fit without in-popup scrolling;
still overflow-y:auto so very tall content scrolls rather than clipping. Scoped to
the mobile dvh rule; desktop unaffected. Adds a source-level guard test.
Contributor stage; gate-pass. Co-authored-by: nankingjing <nankingjing@users.noreply.github.com>