Update template by id

Update one variant's components by its Meta id. Name, language and category cannot change.

Meta only allows editing templates in APPROVED, REJECTED or PAUSED state; an approved template can be edited once per 24 hours and up to 10 times per 30 days. A successful update sends the variant back to Meta for review, so the status returned here is normally PENDING. The final outcome arrives on the whatsapp.template.status_updated webhook (which carries the variant's templateId and language). A variant already in PENDING cannot be edited again until Meta finishes reviewing it.