fix(create): prevent duplicate rapid submissions

web/src/pages/create/creation-submit-gate.ts

@@ -0,0 +1,14 @@
+export function createCreationSubmitGate() {
+    let locked = false;
+
+    return {
+        tryAcquire() {
+            if (locked) return false;
+            locked = true;
+            return true;
+        },
+        release() {
+            locked = false;
+        },
+    };
+}