[compiler][playground] (2/N) Config override panel (facebook#34344)

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## Summary

Part 2 of adding a "Config Override" panel to the React compiler
playground. Added sync from the config editor (still only accessible
with the "showConfig" param) to the main source code editor. Adding a
valid config to the editor will add/replace the `@OVERRIDE` pragma above
the source code. Additionally refactored the old implementation to
remove `useEffect`s and unnecessary renders.

Realized upon testing that the user experience is quite jarring,
planning to add a `sync` button in the next PR to fix this.

## How did you test this change?

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https://github.com/user-attachments/assets/a71b1b5f-0539-4c00-8d5c-22426f0280f9

DiffTrain build for [ac3e705](facebook@ac3e705)

Author: pull[bot]

compiled-rn/VERSION_NATIVE_FB

@@ -1 +1 @@
-19.2.0-native-fb-7697a9f6-20250903
+19.2.0-native-fb-ac3e705a-20250902

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

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<2846339d2c1433f6d42cd523b35db042>>
+ * @generated SignedSource<<5374a693e663652ad94f96ea4467a742>>
  */
 
 "use strict";
@@ -404,5 +404,5 @@ __DEV__ &&
     exports.useFormStatus = function () {
       return resolveDispatcher().useHostTransitionStatus();
     };
-    exports.version = "19.2.0-native-fb-7697a9f6-20250903";
+    exports.version = "19.2.0-native-fb-ac3e705a-20250902";
   })();

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

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<7000fec2a4e4dd428acd413b8cf3abcc>>
+ * @generated SignedSource<<ff60bb06008c92bf24891738d4e66467>>
  */
 
 "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-7697a9f6-20250903";
+exports.version = "19.2.0-native-fb-ac3e705a-20250902";

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

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<7000fec2a4e4dd428acd413b8cf3abcc>>
+ * @generated SignedSource<<ff60bb06008c92bf24891738d4e66467>>
  */
 
 "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-7697a9f6-20250903";
+exports.version = "19.2.0-native-fb-ac3e705a-20250902";