feat(clients): add bulk enable/disable and move selection actions into More menu

Add bulkEnable/bulkDisable named endpoints backed by a shared internal impl, and consolidate the per-selection actions (attach, detach, add to group, ungroup, enable, disable, adjust, sub links) into the clients table's More dropdown so the toolbar only shows the selection count and delete. Translate the new enable/disable confirm dialogs and toasts across all 13 locales.

internal/web/translation/en-US.json

@@ -816,6 +816,12 @@
       "attach": "Attach",
       "adjust": "Adjust",
       "subLinks": "Sub links",
+      "enable": "Enable",
+      "disable": "Disable",
+      "bulkEnableConfirmTitle": "Enable {count} clients?",
+      "bulkEnableConfirmContent": "Enables each selected client on every attached inbound. Clients whose quota is exhausted or whose expiry has passed will be disabled again automatically.",
+      "bulkDisableConfirmTitle": "Disable {count} clients?",
+      "bulkDisableConfirmContent": "Disables each selected client on every attached inbound. They lose access immediately but their records and traffic are kept.",
       "selectedCount": "{count} selected",
       "attachSelected": "Attach ({count})",
       "attachToInboundsTitle": "Attach {count} client(s) to inbound(s)",
@@ -875,6 +881,10 @@
         "allTrafficsReset": "All client traffic reset",
         "bulkDeleted": "{count} clients deleted",
         "bulkDeletedMixed": "{ok} deleted, {failed} failed",
+        "bulkEnabled": "{count} clients enabled",
+        "bulkEnabledMixed": "{ok} enabled, {failed} failed",
+        "bulkDisabled": "{count} clients disabled",
+        "bulkDisabledMixed": "{ok} disabled, {failed} failed",
         "bulkCreated": "{count} clients created",
         "bulkCreatedMixed": "{ok} created, {failed} failed",
         "bulkAdjusted": "{count} clients adjusted",