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/app/api/v1/openapi/route.ts

@@ -0,0 +1,14 @@
+import { readFile } from "fs/promises";
+import path from "path";
+import { withApiHandler } from "@/lib/api-handler";
+
+export async function GET(request: Request) {
+  return withApiHandler(request, async () => {
+    const specPath = path.join(process.cwd(), "docs", "api", "openapi.yaml");
+    const spec = await readFile(specPath, "utf8");
+    return new Response(spec, {
+      status: 200,
+      headers: { "Content-Type": "application/yaml; charset=utf-8" },
+    });
+  });
+}