dx-standards-update

Land a rule in the right context/standards/<layer>/<topic>.md. Standards are the rulebook — prescriptive, project-wide, stable, and edited in place (a catalog, not an append-only log). Read foundation/glossary.md for naming (a one-line habit — no section).

Guard. context/standards/ must exist. If it is missing, tell the user to run /dx-init first.

1 — Get the rule (three entry points)

• From the conversation (no argument) — the user said "make this a standard." Lift the rule from what was just discussed; if it is fuzzy, ask one clarifying question, no more.
• From a graduated lesson — a foundation/lessons.md entry that has stopped being "this one time" and become "how we do it here." Read it and carry its rule forward.
• From --from=PATH — read the named file (e.g. a graduated lesson, or another project's context/standards/…) and take the rule from it.

2 — Load the contract (invoke dx-references with knowledge-layer)

Use it for the standards-vs-lessons distinction, the standard entry shape, and the promotion criteria — confirm this rule is recurring and generalized, not a one-off (a one-off stays a lesson).

3 — Place it: layer × topic

Pick the file by layer (global / frontend / backend / testing) × topic (the existing filename it belongs in, e.g. coding-style.md, error-handling.md). Prefer an existing file; create a new <topic>.md only when nothing fits.