feat(ui): add select all / clear all shortcuts for inbound multi-select (#5175)

* feat(ui): add select all / clear all shortcuts for inbound multi-select

Adds 'Select all' and 'Clear all' buttons above the inbound multi-select in:
- ClientFormModal (add/edit client)
- BulkAttachInboundsModal (bulk attach clients to inbounds)
- BulkDetachInboundsModal (bulk detach clients from inbounds)
- ClientBulkAddModal (add bulk clients)

Extracts the repeated button logic into a reusable SelectAllClearButtons component.

Includes i18n keys for all 13 supported languages with proper translations.

Closes #5144

* refactor(form): decouple SelectAllClearButtons labels and harden select-all

Accept optional selectAllLabel/clearLabel props so the generic form component is not tied to the client-inbound i18n keys (defaults unchanged). Compute the all-selected state by checking every option is present and union the current value on select-all, so it stays correct if value holds ids outside options.

---------

Co-authored-by: Sanaei <ho3ein.sanaei@gmail.com>

frontend/src/components/form/index.ts

@@ -1,3 +1,4 @@
 export { default as DateTimePicker } from './DateTimePicker';
 export { default as JsonEditor } from './JsonEditor';
 export { default as HeaderMapEditor } from './HeaderMapEditor';
+export { default as SelectAllClearButtons } from './SelectAllClearButtons';