feat: add bulk delete for session manager (#1693)

* feat: add bulk delete for session manager

* fix: address batch delete review issues

* fix: keep session list in sync after batch delete

src/i18n/locales/en.json

@@ -613,6 +613,16 @@
     "searchSessions": "Search sessions",
     "providerFilterAll": "All",
     "sessionList": "Sessions",
+    "manageBatchTooltip": "Enter batch management",
+    "exitBatchModeTooltip": "Exit batch management",
+    "batchModeHint": "Select sessions to delete",
+    "selectForBatch": "Select session",
+    "selectedCount": "{{count}} selected",
+    "selectAllFiltered": "Select all",
+    "clearFilteredSelection": "Clear selection",
+    "clearSelection": "Clear",
+    "deleteSelected": "Delete",
+    "batchDeleting": "Deleting...",
     "loadingSessions": "Loading sessions...",
     "noSessions": "No sessions found",
     "selectSession": "Select a session to view details",
@@ -641,6 +651,12 @@
     "deleteConfirmAction": "Delete session",
     "sessionDeleted": "Session deleted",
     "deleteFailed": "Failed to delete session: {{error}}",
+    "batchDeleteConfirmTitle": "Delete selected sessions",
+    "batchDeleteConfirmMessage": "This will permanently delete {{count}} selected local sessions.\n\nThis action cannot be undone.",
+    "batchDeleteConfirmAction": "Delete selected",
+    "batchDeleteSuccess": "Deleted {{count}} sessions",
+    "batchDeleteFailed": "{{failed}} sessions could not be deleted",
+    "batchDeleteRequestFailed": "Batch delete failed. Please try again later.",
     "loadingMessages": "Loading transcript...",
     "emptySession": "No messages available",
     "clickToCopyPath": "Click to copy path",