feat(18-01): add documentTemplates table and relation to schema.ts

- Add document_templates pgTable with 7 columns: id, name, formTemplateId, signatureFields, archivedAt, createdAt, updatedAt
- formTemplateId FK references formTemplates.id with no onDelete cascade
- signatureFields typed as SignatureFieldData[] via jsonb, nullable (template starts empty)
- archivedAt nullable timestamp for soft-delete (NULL = active)
- Add documentTemplatesRelations joining to formTemplates

teressa-copeland-homes/src/lib/db/schema.ts

@@ -98,6 +98,20 @@ export const formTemplates = pgTable("form_templates", {
   updatedAt: timestamp("updated_at").defaultNow().notNull(),
 });
 
+export const documentTemplates = pgTable("document_templates", {
+  id: text("id").primaryKey().$defaultFn(() => crypto.randomUUID()),
+  name: text("name").notNull(),
+  formTemplateId: text("form_template_id").notNull().references(() => formTemplates.id),
+  signatureFields: jsonb("signature_fields").$type<SignatureFieldData[]>(),
+  archivedAt: timestamp("archived_at"),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().notNull(),
+});
+
+export const documentTemplatesRelations = relations(documentTemplates, ({ one }) => ({
+  formTemplate: one(formTemplates, { fields: [documentTemplates.formTemplateId], references: [formTemplates.id] }),
+}));
+
 /** Shape of each entry in documents.signers JSONB array. */
 export interface DocumentSigner {
   email: string;