feat(sdk,studio): ws-4 — add history:false option; disable unused sdk undo in studio

Co-authored-by: Miguel Ángel <miguel07alm@protonmail.com>

Author: vanceingalls

packages/sdk/src/session.ts

@@ -48,6 +48,12 @@ export interface OpenCompositionOptions {
   trackedOrigins?: unknown[];
   /** Auto-coalesce window for history entries (ms). Default: 300. */
   coalesceMs?: number;
+  /**
+   * Pass `false` to skip attaching the history module (undo/redo).
+   * Default: history is attached in standalone (non-embedded) mode.
+   * Use when the host owns the undo stack and SDK undo is dead weight.
+   */
+  history?: false;
 }
 
 // ─── Implementation ───────────────────────────────────────────────────────────
@@ -495,7 +501,7 @@ export async function openComposition(
 
   const isEmbedded = opts?.overrides !== undefined;
 
-  if (!isEmbedded) {
+  if (!isEmbedded && opts?.history !== false) {
     const history = createHistory(session, {
       coalesceMs: opts?.coalesceMs ?? 300,
       trackedOrigins: opts?.trackedOrigins,

packages/studio/src/hooks/useSdkSession.ts

@@ -97,7 +97,9 @@ export function useSdkSession(
         // 'change' AND Studio writes explicitly) and race on disk; it would
         // also write the full active-composition serialization to the fixed
         // persistPath even when an edit targeted a sub-composition file.
-        const comp = await openComposition(content);
+        // Studio's editHistory is the authoritative undo stack — SDK history
+        // is unused dead weight here (forceReloadSdkSession discards it on undo).
+        const comp = await openComposition(content, { history: false });
         // Cleanup may have fired while openComposition was awaited; dispose immediately.
         if (cancelled) {
           comp.dispose();