feat(eoi): dual-path generateAndSign (inapp + documenso-template)

generateAndSign now accepts a `pathway` parameter:

- `inapp` (existing): resolve in-app template -> pdfme -> MinIO -> Documenso
  createDocument + sendDocument.
- `documenso-template` (new): build EOI context from interestId, assemble
  the Documenso template payload, and call Documenso's
  /api/v1/templates/{id}/generate-document. Documenso owns the PDF; we
  still record a documents row for tracking.

Adds generateDocumentFromTemplate helper to the Documenso client and new
env vars (DOCUMENSO_TEMPLATE_ID_EOI + client/developer/approval recipient
IDs) with defaults matching the legacy flow. Covered by 6 new integration
tests (637/637 green).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/lib/env.ts

@@ -24,6 +24,10 @@ const envSchema = z.object({
   DOCUMENSO_API_URL: z.string().url(),
   DOCUMENSO_API_KEY: z.string().min(1),
   DOCUMENSO_WEBHOOK_SECRET: z.string().min(16),
+  DOCUMENSO_TEMPLATE_ID_EOI: z.coerce.number().int().positive().default(8),
+  DOCUMENSO_CLIENT_RECIPIENT_ID: z.coerce.number().int().positive().default(192),
+  DOCUMENSO_DEVELOPER_RECIPIENT_ID: z.coerce.number().int().positive().default(193),
+  DOCUMENSO_APPROVAL_RECIPIENT_ID: z.coerce.number().int().positive().default(194),
 
   // Email
   SMTP_HOST: z.string().min(1),