Fixes #13752 Removes the standalone `working_hours` API endpoint instead of fixing only the callback typo in `WorkingHoursController`. ## Why The route is not used by the dashboard. The supported product flow already updates business hours through `PATCH /api/v1/accounts/:account_id/inboxes/:id`. The standalone endpoint was already unusable in practice: - The controller callback pointed to the wrong method. - Fixing that callback alone would still leave the endpoint blocked by missing `WorkingHourPolicy` authorization. - Keeping the route would preserve unsupported API surface without making the product flow better. ## What this change does - Removes `PATCH/PUT /api/v1/accounts/:account_id/working_hours/:id`. - Deletes `Api::V1::Accounts::WorkingHoursController`. - Leaves the inbox working-hours update path unchanged. Compatibility note: this removes an undocumented endpoint that was already unusable in practice. Working-hours updates should continue to go through the supported inbox update API. ## Validation - Ran `bin/rails routes -g working_hours` and confirmed the standalone working-hours API route is no longer present. - Searched for remaining `WorkingHoursController` and `resources :working_hours` references. --------- Co-authored-by: easonysliu <easonysliu@tencent.com> Co-authored-by: Sojan Jose <sojan@pepalo.com>