fix(autosave) : retry constellation version conflicts

hooks/use-autosave.ts

@@ -3,6 +3,7 @@
 import { useEffect, useEffectEvent, useRef, useState } from "react";
 import { toast } from "sonner";
 
+import { saveWithConflictRetry } from "@/lib/editor/autosave";
 import { parseLocalDraft as parseStoredDraft, serializeLocalDraft } from "@/lib/editor/local-draft";
 
 export type AutosaveState = "saved" | "unsaved" | "saving" | "incomplete" | "error";
@@ -95,7 +96,9 @@ export function useAutosave<Value, Draft = Value>({
     setSaving(true);
     setErrorFingerprint(null);
     try {
-      const result = await persist(snapshot, version);
+      const attempt = await saveWithConflictRetry(persist, snapshot, version);
+      const result = attempt.response;
+      if (attempt.retried) setVersion(attempt.version);
       if (result.status === "error" || result.status === "conflict") {
         if (result.currentVersion) setVersion(result.currentVersion);
         setErrorFingerprint(snapshotFingerprint);