draw_path, draw_shape and object.setProps take opacity in percent (0-100),
but the document.inspect / document.node summary behind doc_inspect,
inspect_document and vectorcraft://object/{id} reported the stored 0-1
fraction under the same name. An agent that read 0.55 and wrote it back
got a nearly invisible object.
The summary now adds opacityPct (0-100, rounded to 1/100 of a percent)
beside the unchanged opacity, and the tool, resource and command
descriptions say which scale each field uses. Round-trip test in the mcp
crate: draw at 55 %, read 55 back from doc_inspect, inspect_document and
the object resource, write it back unchanged.