[kernel-847] add functionality to get cursor position via API

[archandatta]

Note

Medium Risk
Introduces a new host-input API surface that shells out to xdotool; main risk is runtime fragility across environments and contention with other input operations despite mutex serialization.

Overview
Adds a new Computer API endpoint POST /computer/get_mouse_position that returns the current cursor coordinates as {x,y}.

Implements the handler by running xdotool getmouselocation --shell, parsing the output via a new parseMousePosition helper (with input locking and error reporting), and updates generated OAPI client/server types plus unit tests for the parser.

^{Written by Cursor Bugbot for commit a372758. This will update automatically on new commits. Configure here.}

[Sayan-]

lgtm!