checkMapping takes kind absent, hybrid or draft. A draft has a name and one
or more prefixes and no books, and comes back with books []. A prefix inside
or holding another entry's book refuses library-playground-other-universe,
which replaces library-playground-outside-book. A prefix equal to a book or
holding its own refuses library-mapping-invalid, as does a draft source.
classify returns a playground file's entry and the book holding its prefix,
or null at universe level and in a draft.
Doc only, Sage's sage/row218 89ba79d94 (three commits squashed). Webby APPROVE round 1 (webby-0075,
rev 2848), round 2 (webby-0077, rev 2856) and round 3 (webby-0078, rev 2860). docs/case2/SETUP-SHEET.md
tells Melanie what the agents read, the playground, link and property forms, and what changes for
Bean and Chet, with M5's 1,200 character reply total (mos-1165). It goes to her only after C2-06
lands and on Jason's go (#419). docs/case2/SURVEY-RUN.md is design 10 step 7's run sheet: the
bare mirror as the source, a node check, output lines and refusals from survey.mjs. Claim sources
and rulings are in agents/sage/work/queue-218/BUILD.md. No test reads either doc path.
jason.woltje