The tappable mode row used a bare `clickable`, which declares no role. TalkBack read it as
two pieces of text with nothing to say it could be activated, so the only way to correct a
wrong mode was invisible to anyone using a screen reader - and the row had just become the
only way to reach that field.
Role.Button plus an onClickLabel naming the action. The label lives in the resource files
like every other user-visible string.
Caught by self-review against the project's own accessibility pattern in Components.kt
rather than by a test; Compose UI is not unit-tested here, so this class of defect is only
ever found by reading.
mckero
a3e3932f73