Action::Overview shells out to `ipc call overview toggle`. The only handler
here was `search`, so that call reached nothing and the three-finger tap
did nothing, without an error anyone would see.
It has been invisible from the device because the shipped sessiond has no
`gesture` verb yet and refuses the op long before the executor runs, so
only the first half of the break was observable.
This makes the existing binding reach the surface it already names. What
the tap should raise is TASK-55 Q1 and is not decided here.
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