feat: upload template via API (#1842)

Allow users to upload templates via both v1 and v2 APIs. Similar to
uploading documents.

packages/api/v1/contract.ts

@@ -1,5 +1,10 @@
 import { initContract } from '@ts-rest/core';
 
+import {
+  ZCreateTemplateV2RequestSchema,
+  ZCreateTemplateV2ResponseSchema,
+} from '@documenso/trpc/server/template-router/schema';
+
 import {
   ZAuthorizationHeadersSchema,
   ZCreateDocumentFromTemplateMutationResponseSchema,
@@ -87,6 +92,18 @@ export const ApiContractV1 = c.router(
       summary: 'Upload a new document and get a presigned URL',
     },
 
+    createTemplate: {
+      method: 'POST',
+      path: '/api/v1/templates',
+      body: ZCreateTemplateV2RequestSchema,
+      responses: {
+        200: ZCreateTemplateV2ResponseSchema,
+        401: ZUnsuccessfulResponseSchema,
+        404: ZUnsuccessfulResponseSchema,
+      },
+      summary: 'Create a new template and get a presigned URL',
+    },
+
     deleteTemplate: {
       method: 'DELETE',
       path: '/api/v1/templates/:id',