feat: journal dashboard widgets, agent polish, and edit-mode live previews

Journal dashboard widgets and quick-add; rich-text quick-add dialogs.

Dashboard draft sync for live edit previews; assistant bubble + API tools.

Journal UX: stress slider, mood grid, query cap fix.

src/lib/assistant-preference.ts

@@ -0,0 +1,13 @@
+import { eq } from "drizzle-orm";
+import { db } from "@/lib/db";
+import { users } from "@/modules/_core/schema";
+
+export async function getAssistantEnabled(userId: string): Promise<boolean> {
+  const [row] = await db
+    .select({ assistantEnabled: users.assistantEnabled })
+    .from(users)
+    .where(eq(users.id, userId))
+    .limit(1);
+
+  return row?.assistantEnabled ?? false;
+}