feat: add "All Mail" view

app/(main)/[locale]/page.tsx

@@ -11,8 +11,9 @@ import type { ComposerDraftData } from "@/components/email/email-composer";
 import { ProtocolAccountPicker } from "@/components/protocol/protocol-account-picker";
 import { ThreadConversationView } from "@/components/email/thread-conversation-view";
 import { MobileHeader } from "@/components/layout/mobile-header";
-import { ThreadGroup, Email, isUnifiedMailboxId, UNIFIED_ROLE_BY_ID } from "@/lib/jmap/types";
+import { ThreadGroup, Email, isUnifiedMailboxId, UNIFIED_ROLE_BY_ID, ALL_MAIL_MAILBOX_ID } from "@/lib/jmap/types";
 import { useAccountStore } from "@/stores/account-store";
+import { usePolicyStore } from "@/stores/policy-store";
 import type { UnifiedAccountClient } from "@/lib/unified-mailbox";
 import { KeyboardShortcutsModal } from "@/components/keyboard-shortcuts-modal";
 import { useEmailStore, buildUnifiedAccountClients } from "@/stores/email-store";
@@ -341,7 +342,10 @@ export default function Home() {
   useProMultiAccountMailboxes();
 
   const enableUnifiedMailbox = useSettingsStore((s) => s.enableUnifiedMailbox);
+  const enableAllMailView = useSettingsStore((s) => s.enableAllMailView);
   const delayedSendSupported = client?.hasDelayedSend() ?? true;
+  const allMailViewEnabled = usePolicyStore((s) => s.isFeatureEnabled('allMailViewEnabled'));
+  const showAllMailMailbox = allMailViewEnabled && enableAllMailView;
   const activeEmails = isScheduledView ? scheduledEmails : emails;
   const activeHasMore = isScheduledView ? scheduledHasMore : hasMoreEmails;
   const activeIsLoading = isScheduledView ? isLoadingScheduled : isLoading;
@@ -2213,7 +2217,11 @@ export default function Home() {
   }
 
   // Get current mailbox name for mobile header
-  const currentMailboxName = isScheduledView ? t('sidebar.scheduled') : mailboxes.find(m => m.id === selectedMailbox)?.name || "Inbox";
+  const currentMailboxName = isScheduledView
+    ? t('sidebar.scheduled')
+    : selectedMailbox === ALL_MAIL_MAILBOX_ID
+      ? t('sidebar.mailboxes.all_mail')
+      : mailboxes.find(m => m.id === selectedMailbox)?.name || "Inbox";
   const isFocusedMailLayout = mailLayout === 'focus';
   const isHorizontalMailLayout = mailLayout === 'horizontal' && !isMobile && !isTablet;
   const hasViewerContent = showComposer || Boolean(conversationThread) || Boolean(selectedEmail);
@@ -2475,6 +2483,7 @@ export default function Home() {
               selectedKeyword={selectedKeyword}
               scheduledTotal={scheduledTotal}
               showScheduledMailbox={delayedSendSupported}
+              showAllMailMailbox={showAllMailMailbox}
               onMailboxSelect={handleMailboxSelect}
               onTagSelect={handleTagSelect}
               onUnreadFilterClick={handleUnreadFilterClick}

app/(main)/[locale]/settings/page.tsx

@@ -183,6 +183,7 @@ const tabSearchPaths: Record<Tab, string[]> = {
     'settings.appearance.hide_account_switcher',
     'settings.appearance.show_rail_account_list',
     'settings.appearance.unified_mailbox',
+    'settings.appearance.all_mail',
     'settings.appearance.colorful_sidebar_icons',
     'settings.email_behavior.mail_layout',
   ],

app/(main)/admin/_tabs/policy.tsx

@@ -21,6 +21,7 @@ const FEATURE_GATE_LABELS: Partial<Record<keyof FeatureGates, { label: string; d
   folderIconsEnabled: { label: 'Folder Icons', description: 'Allow custom folder icon picker' },
   hoverActionsConfigEnabled: { label: 'Hover Actions Config', description: 'Allow users to customize email hover actions' },
   filesEnabled: { label: 'Files (WebDAV)', description: 'Enable file storage via WebDAV. WARNING: Large uploads can cause Stalwart/RocksDB instability. Not recommended for production.' },
+  allMailViewEnabled: { label: 'All Mail View', description: 'Show a virtual "All Mail" folder that merges messages from across an account’s folders into one list. Users choose which folders are included.' },
 };
 
 const RESTRICTABLE_SETTINGS = [