fix: default to user timezone (#1559)

Passes the timezone of the user uploading the document/template via the
UI to the server.

If the user uploads a document/template via the API and doesn't set a
timezone, it defaults to `Etc/UTC`.

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

@@ -66,6 +66,7 @@ export const ZCreateDocumentMutationSchema = z.object({
   title: z.string().min(1),
   documentDataId: z.string().min(1),
   teamId: z.number().optional(),
+  timezone: z.string().optional(),
 });
 
 export type TCreateDocumentMutationSchema = z.infer<typeof ZCreateDocumentMutationSchema>;