One letter surface for every role: LetterCanvasComponent renders the
org template's letterhead/signature/footer around the case-type
sections, with editableRegions content|template|none. public/letter.css
is the FE⇄BE rendering contract (WP-25 inlines it verbatim).
letter-preview deleted — its read-only rendering absorbed into 'none'
mode. brief.machine.ts byte-identical; orgTemplate parses at the
adapter boundary and lives beside the machine in BriefStore.
Also fixes passage-picker multi-select (checkboxes all shared
id="undefined", so labels only toggled the first box) and keeps the
±page-break marks from drawing through canvas content.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Second template axis (org identity: letterhead, footer, signature,
margins) server-side: OrgTemplateStore with JSON version history,
publish/rollback, sent-brief version pinning, admin role + capability,
5 admin endpoints, org-logo upload category. FE seam widened only
(Role/Capability unions, interceptor); WP-24/26 consume it.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
