Introduce a commercial license option alongside AGPL-3.0-only, require a
CLA for contributors, and document the terms in COMMERCIAL.md and
NOTICE. Add a script to stamp SPDX headers on Go files and apply it
across the tree.
Every form on both surfaces is now a declared FormSpec in
internal/forms, rendered through the shared form part and parsed
by its handler through the same declaration. Create and edit
share one field list, refusals answer 422 with values carried
back, and layout, buttons and errors come from one part.
Also adds the form registry with its invariant and route-mapping
tests, the raw-form, filler-copy and Go em-dash lint rules,
declared action triggers, and the capture-coverage cross-check.
The forms-library change is archived under
openspec/changes/archive/2026-09-05-forms-library.
cgalo5758