feat: P2.2 Create Appointment from Email + P2.4 Calendar Dashlet + P2.12 Action Wheel + P2.14 Share Files

- P2.2: 'Create Appointment' button in email viewer → pre-fills event modal
  with subject, body, participants, date. calendar-store newEventPrefill state.
- P2.4: MiniCalendarDashlet in sidebar bottom — month grid with event dots,
  day click navigates to calendar. Collapsible, respect firstDayOfWeek.
- P2.12: Custom radial menu (components/ui/radial-menu.tsx) — circular SVG
  menu with keyboard nav, animations. Wired into email-list, contact-list,
  file-browser, calendar-month-view right-click handlers.
- P2.14: 'Send as Attachment' button in file browser — opens compose tab
  with selected files pre-attached via Pro tab store.

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

@@ -11,6 +11,7 @@ import { useAuthStore, redirectToLogin } from "@/stores/auth-store";
 import { useAccountStore } from "@/stores/account-store";
 import { useEmailStore } from "@/stores/email-store";
 import { useFileStore } from "@/stores/file-store";
+import { useProTabStore } from "@/stores/pro-tab-store";
 import { toast } from "@/stores/toast-store";
 import { cn, formatFileSize } from "@/lib/utils";
 import { NavigationRail } from "@/components/layout/navigation-rail";
@@ -411,6 +412,31 @@ export default function FilesPage() {
     await shareResource(id, principalId, rights);
   }, [shareResource]);
 
+  const handleSendAsAttachment = useCallback((names: string[]) => {
+    const store = useFileStore.getState();
+    const fileAtts = names
+      .map((name) => {
+        const r = store.resources.find((res) => res.name === name);
+        if (!r || r.isDirectory || !r.blobId) return null;
+        return {
+          blobId: r.blobId,
+          name: r.name,
+          type: r.contentType || "application/octet-stream",
+          size: r.contentLength,
+        };
+      })
+      .filter(Boolean) as Array<{ blobId: string; name: string; type: string; size: number }>;
+
+    if (fileAtts.length === 0) return;
+
+    useProTabStore.getState().openComposeTab({
+      sessionId: Date.now(),
+      mode: "compose",
+      replyTo: { attachments: fileAtts },
+      title: fileAtts.length === 1 ? fileAtts[0].name : `${fileAtts.length} attachments`,
+    });
+  }, []);
+
   // Pro shell only: all connected accounts are equal top-level entries at
   // the root. The root path "/" itself is a cross-account picker - no
   // account's files are shown until the user enters one.
@@ -554,6 +580,7 @@ export default function FilesPage() {
                   ownAccountId={filesAccountId}
                   sharingEnabled={sharingEnabled}
                   onShare={handleShare}
+                  onSendAsAttachment={handleSendAsAttachment}
                 />
                 </div>
               )}