Development record

The symlink refusal on the reading trees covers directories but not disposition files: readDispositions keeps a symlinked dsp-N.md, the standing computation, promote's state read and the board's exit-condition line then read a file outside the ledger, and the verb accepts a supersedes citation of the link; and a disposition whose supersedes_disposition names itself, or a two-record cycle, retires every standing answer so the item reads as undispositioned, the verb accepts an uncited fresh answer, and the board reports nothing. Lstat and IsRegular in all three readers; treat self-supersession as not well-formed and a non-empty record set with no standing answer as a ledger fault.