feat(home): add prominent "New note" button to dashboard

Add a big "New note" action to the Home screen that creates a new page
and opens it. Since the home screen has no active space, the target
space is resolved from the user's writable spaces (CASL Manage/Page
gate, mirroring the space sidebar): created directly when there is one
writable space, picked from a dropdown when there are several, hidden
when there are none. Menu items are disabled while a create is in
flight to avoid duplicate pages.

- New component features/home/components/new-note-button.tsx
- Render it at the top of pages/dashboard/home.tsx (above the carousel)
- Add i18n keys "New note" / "Create in space" to en-US and ru-RU

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/client/src/features/home/components/new-note-button.tsx

@@ -0,0 +1,111 @@
+import { Button, Menu, Text } from "@mantine/core";
+import { IconPlus } from "@tabler/icons-react";
+import { createMongoAbility } from "@casl/ability";
+import { useNavigate } from "react-router-dom";
+import { useTranslation } from "react-i18next";
+import { useGetSpacesQuery } from "@/features/space/queries/space-query.ts";
+import { useCreatePageMutation } from "@/features/page/queries/page-query.ts";
+import { buildPageUrl } from "@/features/page/page.utils.ts";
+import { ISpace } from "@/features/space/types/space.types.ts";
+import {
+  SpaceAbility,
+  SpaceCaslAction,
+  SpaceCaslSubject,
+} from "@/features/space/permissions/permissions.type.ts";
+import { CustomAvatar } from "@/components/ui/custom-avatar.tsx";
+import { AvatarIconType } from "@/features/attachments/types/attachment.types.ts";
+
+// A space is writable when the member's CASL rules allow managing pages —
+// mirrors the create-page gate used in the space sidebar.
+function canCreatePage(space: ISpace): boolean {
+  const ability = createMongoAbility<SpaceAbility>(
+    (space.membership?.permissions ?? []) as any,
+  );
+  return ability.can(SpaceCaslAction.Manage, SpaceCaslSubject.Page);
+}
+
+// Prominent home-screen action to create a new note (page). Because the home
+// screen has no active space, the target space is resolved from the user's
+// writable spaces: created directly when there is one, picked from a dropdown
+// when there are several.
+export default function NewNoteButton() {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+  const createPageMutation = useCreatePageMutation();
+  const { data } = useGetSpacesQuery({ limit: 100 });
+
+  const writableSpaces = (data?.items ?? []).filter(canCreatePage);
+
+  const createNote = async (space: ISpace) => {
+    try {
+      // `spaceId` is accepted by the create-page endpoint but is not part of
+      // the shared `IPageInput` type; cast to satisfy the mutation signature.
+      const createdPage = await createPageMutation.mutateAsync({
+        spaceId: space.id,
+      } as any);
+      navigate(buildPageUrl(space.slug, createdPage.slugId, createdPage.title));
+    } catch {
+      // useCreatePageMutation already surfaces a red notification on error.
+    }
+  };
+
+  // No writable space → nothing to create in; render nothing.
+  if (writableSpaces.length === 0) return null;
+
+  const isPending = createPageMutation.isPending;
+
+  // Exactly one writable space → create directly, no picker needed.
+  if (writableSpaces.length === 1) {
+    return (
+      <Button
+        fullWidth
+        size="md"
+        leftSection={<IconPlus size={18} />}
+        loading={isPending}
+        onClick={() => createNote(writableSpaces[0])}
+      >
+        {t("New note")}
+      </Button>
+    );
+  }
+
+  // Multiple writable spaces → pick the target space from a dropdown.
+  return (
+    <Menu shadow="md" width="target" position="bottom-start">
+      <Menu.Target>
+        <Button
+          fullWidth
+          size="md"
+          leftSection={<IconPlus size={18} />}
+          loading={isPending}
+        >
+          {t("New note")}
+        </Button>
+      </Menu.Target>
+      <Menu.Dropdown>
+        <Menu.Label>{t("Create in space")}</Menu.Label>
+        {writableSpaces.map((space) => (
+          <Menu.Item
+            key={space.id}
+            disabled={isPending}
+            leftSection={
+              <CustomAvatar
+                name={space.name}
+                avatarUrl={space.logo}
+                type={AvatarIconType.SPACE_ICON}
+                color="initials"
+                variant="filled"
+                size={20}
+              />
+            }
+            onClick={() => createNote(space)}
+          >
+            <Text size="sm" lineClamp={1}>
+              {space.name}
+            </Text>
+          </Menu.Item>
+        ))}
+      </Menu.Dropdown>
+    </Menu>
+  );
+}