Development record

`.abcd/development/brief/04-surfaces/01-ahoy.md:34` lists `abcd ahoy shared-folder` as shipped, and the chapter says nothing else about it beyond the generated appendix (:1587, :1671). What the verb is for, what it writes and what `--person` means are stated only in `commands/ahoy.md:1475` and in the verb's help; `.abcd/development/brief/04-surfaces/17-guard.md:207` and `.abcd/development/brief/04-surfaces/27-implement.md:697` mention the folder in passing.