feat(inbounds): add multi-select and bulk delete

Mirror the clients page: checkbox selection on the desktop table and on
mobile cards, with a danger Delete button in the toolbar that removes all
selected inbounds in one call.

Backend adds POST /panel/api/inbounds/bulkDel, which loops the existing
DelInbound per id (xray restarts at most once) and returns {deleted,
skipped}. Frontend shows a confirm modal plus a result toast, clears the
selection on success, adds bulk-delete i18n keys across all 13 languages,
and documents the endpoint in the in-panel API docs.

web/translation/id-ID.json

@@ -296,6 +296,10 @@
       "deleteConfirmContent": "Tindakan ini menghapus inbound beserta semua kliennya. Tidak dapat dibatalkan.",
       "resetConfirmTitle": "Reset trafik \"{remark}\"?",
       "resetConfirmContent": "Mengatur ulang counter unggah/unduh ke 0 untuk inbound ini.",
+      "selectedCount": "{count} dipilih",
+      "selectAll": "Pilih semua",
+      "bulkDeleteConfirmTitle": "Hapus {count} inbound?",
+      "bulkDeleteConfirmContent": "Tindakan ini menghapus inbound yang dipilih beserta semua kliennya. Tidak dapat dibatalkan.",
       "cloneConfirmTitle": "Klon inbound \"{remark}\"?",
       "cloneConfirmContent": "Membuat salinan dengan port baru dan daftar klien kosong.",
       "delAllClients": "Hapus Semua Klien",
@@ -421,6 +425,8 @@
         "inboundsUpdateSuccess": "Inbound berhasil diperbarui",
         "inboundUpdateSuccess": "Inbound berhasil diperbarui",
         "inboundCreateSuccess": "Inbound berhasil dibuat",
+        "bulkDeleted": "{count} inbound dihapus",
+        "bulkDeletedMixed": "{ok} dihapus, {failed} gagal",
         "inboundDeleteSuccess": "Inbound berhasil dihapus",
         "inboundClientAddSuccess": "Klien inbound telah ditambahkan",
         "inboundClientDeleteSuccess": "Klien inbound telah dihapus",