feat: add support for attachments in template management

- Enhanced TemplateEditForm to include attachments in the template data.
- Updated createDocumentFromTemplate to handle attachment creation.
- Modified updateTemplate to manage attachment updates and deletions.
- Integrated attachments into ZTemplateSchema and ZAddTemplateSettingsFormSchema for validation.
- Improved getTemplateById to fetch attachments alongside other template data.

packages/trpc/server/template-router/schema.ts

@@ -14,6 +14,7 @@ import {
   ZTemplateManySchema,
   ZTemplateSchema,
 } from '@documenso/lib/types/template';
+import AttachmentSchema from '@documenso/prisma/generated/zod/modelSchema/AttachmentSchema';
 import { TemplateDirectLinkSchema } from '@documenso/prisma/generated/zod/modelSchema/TemplateDirectLinkSchema';
 
 import {
@@ -154,6 +155,16 @@ export const ZUpdateTemplateRequestSchema = z.object({
         .optional(),
       type: z.nativeEnum(TemplateType).optional(),
       useLegacyFieldInsertion: z.boolean().optional(),
+      attachments: AttachmentSchema.pick({
+        id: true,
+        label: true,
+        url: true,
+      })
+        .extend({
+          formId: z.string().min(1),
+        })
+        .array()
+        .optional(),
     })
     .optional(),
   meta: z