[playground] bug fixes & UX improvements (facebook#34499)

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## Summary

Made many small changes to the compiler playground to improve user
experience. Removed any "Loading" indicators that would flash in before
a component would finish loading in. Additionally, before users would
see the "Show Internals" button toggling from false to true if they had
set it at true previously. I was able to refactor the URL/local storage
loading so that the `Store` would be fully initialized before the
components would load in.

Attempted to integrate `<Activity>` into showing/hiding these different
editors, but the current state of [monaco
editors](https://github.com/suren-atoyan/monaco-react) does not allow
for this. I created an issue for them to address:
suren-atoyan/monaco-react#753

Added a debounce to the config editor so every key type wouldn't cause
the output panel to respond instantly. Users can type for 500 ms before
an error is thrown at them.

<!--
Explain the **motivation** for making this change. What existing problem
does the pull request solve?
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## How did you test this change?

Here is what loading the page would look like before (not sure why its
so blurry):

https://github.com/user-attachments/assets/58f4281a-cc02-4141-b9b5-f70d6ace12a2

Here is how it looks now:

https://github.com/user-attachments/assets/40535165-fc7c-44fb-9282-9c7fa76e7d53

Here is the debouncing:

https://github.com/user-attachments/assets/e4ab29e4-1afd-4249-beca-671fb6542f5e

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their output, screenshots / videos if the pull request changes the user
interface.
How exactly did you verify that your PR solves the issue you wanted to
solve?
  If you leave this empty, your PR will very likely be closed.
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DiffTrain build for [6eda534](facebook@6eda534)

Author: pull[bot]

compiled-rn/VERSION_NATIVE_FB

@@ -1 +1 @@
-19.2.0-native-fb-03a96c75-20250918
+19.2.0-native-fb-6eda5347-20250918

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/react-dom/cjs/ReactDOM-dev.js

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<5da1a3dab278e7791017f8a164c67893>>
+ * @generated SignedSource<<fa153f16fe4ea2a275f928e515a988ad>>
  */
 
 "use strict";
@@ -404,5 +404,5 @@ __DEV__ &&
     exports.useFormStatus = function () {
       return resolveDispatcher().useHostTransitionStatus();
     };
-    exports.version = "19.2.0-native-fb-03a96c75-20250918";
+    exports.version = "19.2.0-native-fb-6eda5347-20250918";
   })();

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/react-dom/cjs/ReactDOM-prod.js

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<521dcd9246f14a672468f564fcc57fbf>>
+ * @generated SignedSource<<680df3d17fa3ecae9186ed8a6e69b814>>
  */
 
 "use strict";
@@ -203,4 +203,4 @@ exports.useFormState = function (action, initialState, permalink) {
 exports.useFormStatus = function () {
   return ReactSharedInternals.H.useHostTransitionStatus();
 };
-exports.version = "19.2.0-native-fb-03a96c75-20250918";
+exports.version = "19.2.0-native-fb-6eda5347-20250918";

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/react-dom/cjs/ReactDOM-profiling.js

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<521dcd9246f14a672468f564fcc57fbf>>
+ * @generated SignedSource<<680df3d17fa3ecae9186ed8a6e69b814>>
  */
 
 "use strict";
@@ -203,4 +203,4 @@ exports.useFormState = function (action, initialState, permalink) {
 exports.useFormStatus = function () {
   return ReactSharedInternals.H.useHostTransitionStatus();
 };
-exports.version = "19.2.0-native-fb-03a96c75-20250918";
+exports.version = "19.2.0-native-fb-6eda5347-20250918";

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/react-dom/cjs/ReactDOMClient-dev.js

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<6f7d8cbf18cb804129805df67fe2829e>>
+ * @generated SignedSource<<43877e9be2fe193e68d7b4a26fb14c11>>
  */
 
 /*
@@ -17525,14 +17525,14 @@ ReactDOMHydrationRoot.prototype.unstable_scheduleHydration = function (target) {
 };
 var isomorphicReactPackageVersion$jscomp$inline_2072 = React.version;
 if (
-  "19.2.0-native-fb-03a96c75-20250918" !==
+  "19.2.0-native-fb-6eda5347-20250918" !==
   isomorphicReactPackageVersion$jscomp$inline_2072
 )
   throw Error(
     formatProdErrorMessage(
       527,
       isomorphicReactPackageVersion$jscomp$inline_2072,
-      "19.2.0-native-fb-03a96c75-20250918"
+      "19.2.0-native-fb-6eda5347-20250918"
     )
   );
 ReactDOMSharedInternals.findDOMNode = function (componentOrElement) {
@@ -17554,10 +17554,10 @@ ReactDOMSharedInternals.findDOMNode = function (componentOrElement) {
 };
 var internals$jscomp$inline_2645 = {
   bundleType: 0,
-  version: "19.2.0-native-fb-03a96c75-20250918",
+  version: "19.2.0-native-fb-6eda5347-20250918",
   rendererPackageName: "react-dom",
   currentDispatcherRef: ReactSharedInternals,
-  reconcilerVersion: "19.2.0-native-fb-03a96c75-20250918"
+  reconcilerVersion: "19.2.0-native-fb-6eda5347-20250918"
 };
 if ("undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__) {
   var hook$jscomp$inline_2646 = __REACT_DEVTOOLS_GLOBAL_HOOK__;
@@ -17664,4 +17664,4 @@ exports.hydrateRoot = function (container, initialChildren, options) {
   listenToAllSupportedEvents(container);
   return new ReactDOMHydrationRoot(initialChildren);
 };
-exports.version = "19.2.0-native-fb-03a96c75-20250918";
+exports.version = "19.2.0-native-fb-6eda5347-20250918";

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/react-dom/cjs/ReactDOMClient-prod.js

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<1df38af578f03402ceea78aad46e75a7>>
+ * @generated SignedSource<<fa265f2b5cee7de3970d2f06da94ae74>>
  */
 
 /*
@@ -12888,6 +12888,7 @@ var DefaultAsyncDispatcher = {
   pendingRecoverableErrors = null,
   pendingSuspendedCommitReason = 0,
   pendingDelayedCommitReason = 0,
+  pendingSuspendedViewTransitionReason = null,
   nestedUpdateCount = 0,
   rootWithNestedUpdates = null;
 function requestUpdateLane(fiber) {
@@ -14178,6 +14179,7 @@ function commitRoot(
     pendingEffectsRenderEndTime = completedRenderEndTime;
     pendingSuspendedCommitReason = suspendedCommitReason;
     pendingDelayedCommitReason = 0;
+    pendingSuspendedViewTransitionReason = null;
     (enableComponentPerformanceTrack && 0 !== finishedWork.actualDuration) ||
     0 !== (finishedWork.subtreeFlags & 10256) ||
     0 !== (finishedWork.flags & 10256)
@@ -14367,18 +14369,36 @@ function flushMutationEffects() {
 function flushLayoutEffects() {
   if (2 === pendingEffectsStatus) {
     pendingEffectsStatus = 0;
-    var root = pendingEffectsRoot,
-      finishedWork = pendingFinishedWork,
+    if (enableComponentPerformanceTrack) {
+      var suspendedViewTransitionReason = pendingSuspendedViewTransitionReason;
+      null !== suspendedViewTransitionReason &&
+        ((commitStartTime = now()),
+        !supportsUserTiming ||
+          commitStartTime <= commitEndTime ||
+          console.timeStamp(
+            suspendedViewTransitionReason,
+            commitEndTime,
+            commitStartTime,
+            currentTrack,
+            "Scheduler \u269b",
+            "secondary-light"
+          ));
+    }
+    suspendedViewTransitionReason = pendingEffectsRoot;
+    var finishedWork = pendingFinishedWork,
       lanes = pendingEffectsLanes,
-      cleanUpIndicator = root.pendingIndicator;
-    if (null !== cleanUpIndicator && 0 === root.indicatorLanes) {
+      cleanUpIndicator = suspendedViewTransitionReason.pendingIndicator;
+    if (
+      null !== cleanUpIndicator &&
+      0 === suspendedViewTransitionReason.indicatorLanes
+    ) {
       var prevTransition = ReactSharedInternals.T;
       ReactSharedInternals.T = null;
       var previousPriority = ReactDOMSharedInternals.p;
       ReactDOMSharedInternals.p = 2;
       var prevExecutionContext = executionContext;
       executionContext |= 4;
-      root.pendingIndicator = null;
+      suspendedViewTransitionReason.pendingIndicator = null;
       try {
         cleanUpIndicator();
       } catch (x) {
@@ -14403,9 +14423,13 @@ function flushLayoutEffects() {
             typeof injectedProfilingHooks.markLayoutEffectsStarted &&
           injectedProfilingHooks.markLayoutEffectsStarted(lanes),
           (inProgressLanes = lanes),
-          (inProgressRoot = root),
+          (inProgressRoot = suspendedViewTransitionReason),
           resetComponentEffectTimers(),
-          commitLayoutEffectOnFiber(root, finishedWork.alternate, finishedWork),
+          commitLayoutEffectOnFiber(
+            suspendedViewTransitionReason,
+            finishedWork.alternate,
+            finishedWork
+          ),
           (inProgressRoot = inProgressLanes = null),
           null !== injectedProfilingHooks &&
             "function" ===
@@ -14417,20 +14441,21 @@ function flushLayoutEffects() {
           (ReactSharedInternals.T = cleanUpIndicator);
       }
     }
-    root = pendingEffectsRenderEndTime;
+    suspendedViewTransitionReason = pendingEffectsRenderEndTime;
     finishedWork = pendingSuspendedCommitReason;
     enableComponentPerformanceTrack &&
       ((commitEndTime = now()),
-      (root = 0 === finishedWork ? root : commitStartTime),
+      (suspendedViewTransitionReason =
+        0 === finishedWork ? suspendedViewTransitionReason : commitStartTime),
       (finishedWork = commitEndTime),
       (lanes = 1 === pendingDelayedCommitReason),
       null !== commitErrors
-        ? logCommitErrored(root, finishedWork)
+        ? logCommitErrored(suspendedViewTransitionReason, finishedWork)
         : !supportsUserTiming ||
-          finishedWork <= root ||
+          finishedWork <= suspendedViewTransitionReason ||
           console.timeStamp(
             lanes ? "Commit Interrupted View Transition" : "Commit",
-            root,
+            suspendedViewTransitionReason,
             finishedWork,
             currentTrack,
             "Scheduler \u269b",
@@ -15230,20 +15255,20 @@ function debounceScrollEnd(targetInst, nativeEvent, nativeEventTarget) {
     (nativeEventTarget[internalScrollTimer] = targetInst));
 }
 for (
-  var i$jscomp$inline_1924 = 0;
-  i$jscomp$inline_1924 < simpleEventPluginEvents.length;
-  i$jscomp$inline_1924++
+  var i$jscomp$inline_1930 = 0;
+  i$jscomp$inline_1930 < simpleEventPluginEvents.length;
+  i$jscomp$inline_1930++
 ) {
-  var eventName$jscomp$inline_1925 =
-      simpleEventPluginEvents[i$jscomp$inline_1924],
-    domEventName$jscomp$inline_1926 =
-      eventName$jscomp$inline_1925.toLowerCase(),
-    capitalizedEvent$jscomp$inline_1927 =
-      eventName$jscomp$inline_1925[0].toUpperCase() +
-      eventName$jscomp$inline_1925.slice(1);
+  var eventName$jscomp$inline_1931 =
+      simpleEventPluginEvents[i$jscomp$inline_1930],
+    domEventName$jscomp$inline_1932 =
+      eventName$jscomp$inline_1931.toLowerCase(),
+    capitalizedEvent$jscomp$inline_1933 =
+      eventName$jscomp$inline_1931[0].toUpperCase() +
+      eventName$jscomp$inline_1931.slice(1);
   registerSimpleEvent(
-    domEventName$jscomp$inline_1926,
-    "on" + capitalizedEvent$jscomp$inline_1927
+    domEventName$jscomp$inline_1932,
+    "on" + capitalizedEvent$jscomp$inline_1933
   );
 }
 registerSimpleEvent(ANIMATION_END, "onAnimationEnd");
@@ -19584,16 +19609,16 @@ ReactDOMHydrationRoot.prototype.unstable_scheduleHydration = function (target) {
     0 === i && attemptExplicitHydrationTarget(target);
   }
 };
-var isomorphicReactPackageVersion$jscomp$inline_2335 = React.version;
+var isomorphicReactPackageVersion$jscomp$inline_2341 = React.version;
 if (
-  "19.2.0-native-fb-03a96c75-20250918" !==
-  isomorphicReactPackageVersion$jscomp$inline_2335
+  "19.2.0-native-fb-6eda5347-20250918" !==
+  isomorphicReactPackageVersion$jscomp$inline_2341
 )
   throw Error(
     formatProdErrorMessage(
       527,
-      isomorphicReactPackageVersion$jscomp$inline_2335,
-      "19.2.0-native-fb-03a96c75-20250918"
+      isomorphicReactPackageVersion$jscomp$inline_2341,
+      "19.2.0-native-fb-6eda5347-20250918"
     )
   );
 ReactDOMSharedInternals.findDOMNode = function (componentOrElement) {
@@ -19613,12 +19638,12 @@ ReactDOMSharedInternals.findDOMNode = function (componentOrElement) {
     null === componentOrElement ? null : componentOrElement.stateNode;
   return componentOrElement;
 };
-var internals$jscomp$inline_2342 = {
+var internals$jscomp$inline_2348 = {
   bundleType: 0,
-  version: "19.2.0-native-fb-03a96c75-20250918",
+  version: "19.2.0-native-fb-6eda5347-20250918",
   rendererPackageName: "react-dom",
   currentDispatcherRef: ReactSharedInternals,
-  reconcilerVersion: "19.2.0-native-fb-03a96c75-20250918",
+  reconcilerVersion: "19.2.0-native-fb-6eda5347-20250918",
   getLaneLabelMap: function () {
     for (
       var map = new Map(), lane = 1, index$324 = 0;
@@ -19636,16 +19661,16 @@ var internals$jscomp$inline_2342 = {
   }
 };
 if ("undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__) {
-  var hook$jscomp$inline_2913 = __REACT_DEVTOOLS_GLOBAL_HOOK__;
+  var hook$jscomp$inline_2919 = __REACT_DEVTOOLS_GLOBAL_HOOK__;
   if (
-    !hook$jscomp$inline_2913.isDisabled &&
-    hook$jscomp$inline_2913.supportsFiber
+    !hook$jscomp$inline_2919.isDisabled &&
+    hook$jscomp$inline_2919.supportsFiber
   )
     try {
-      (rendererID = hook$jscomp$inline_2913.inject(
-        internals$jscomp$inline_2342
+      (rendererID = hook$jscomp$inline_2919.inject(
+        internals$jscomp$inline_2348
       )),
-        (injectedHook = hook$jscomp$inline_2913);
+        (injectedHook = hook$jscomp$inline_2919);
     } catch (err) {}
 }
 exports.createRoot = function (container, options) {
@@ -19741,4 +19766,4 @@ exports.hydrateRoot = function (container, initialChildren, options) {
   listenToAllSupportedEvents(container);
   return new ReactDOMHydrationRoot(initialChildren);
 };
-exports.version = "19.2.0-native-fb-03a96c75-20250918";
+exports.version = "19.2.0-native-fb-6eda5347-20250918";