* fix(utils): construct one-shot models off the event loop
* docs(utils): document all one-shot callers and offload scope
Project-file summaries use the shared one-shot helper as well as input
polishing and follow-up suggestions. Include that third caller in the
README and utility guidance, and distinguish the separate skill scanner
and goal evaluator constructors.
Runtime and tests are unchanged. The existing exact-head strict and caller
regressions pass together: 80 passed on Windows with Python 3.12.14.
