v0.3.0 — a result you can trust

Bugs found by running the tool rather than reading it: --verify denied changes you could see (256px compare, 0.2%-of-the-frame threshold); every window was 'active'; a --depth you asked for came back as 'empty'; screenshot --of cropped whatever was in front; an element action reported a success the platform had ignored.

New: ?unexposed names the region an accessibility tree does not describe -- a canvas is in no tree at all, and nothing marked the hole. 'activate' and --window on the coordinate actions, so a coordinate stops landing wherever the pointer happens to be. Every result line now carries what it did: the key combination, the typed text and its length, both ends of a drag, the coordinate actually sent. --version and config show are text like everything else.