refactor(forms): isolate submission persistence

lib/form/submission-write.test.ts

@@ -0,0 +1,9 @@
+import { describe, expect, test } from "bun:test";
+import { formatQueuePosition } from "@/lib/form/form-client";
+
+describe("submission queue position", () => {
+  test("keeps the database one-based position unchanged", () => {
+    expect(formatQueuePosition(1)).toBe("#1");
+    expect(formatQueuePosition(12)).toBe("#12");
+  });
+});