Integra módulo de Resellers (agente eden-commercial)

Resolve conflitos de merge (users.ts, audit.ts, br-documents.ts,
pnpm-lock/workspace.yaml — o worktree partiu de uma base anterior à
existência do módulo de auth/companies, então recriou versões próprias
de arquivos que já existiam no main; mantido o conteúdo do main,
incorporando só a função nova assignUserToReseller). Adiciona
resellersRepo ao barrel @eden/database e ResellersModule ao app.module.ts.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

packages/domain-shared/src/validators/br-documents.ts

@@ -2,7 +2,8 @@
  * CPF/CNPJ format validation (digit-check only — never confirms a document
  * actually exists or belongs to whoever claims it). Ported from the
  * standard Brazilian algorithm, matching the legacy's isValidCPF/
- * isValidCNPJ (eden.md §1 companies, §3 client registration).
+ * isValidCNPJ (eden.md §1 companies, §3 client registration, §1.7
+ * resellers).
  */
 export function onlyDigits(value: string): string {
   return value.replace(/\D/g, "");