dillon1000/react

[compiler][gating] Experimental directive based gating (#33149)

Adds `dynamicGating` as an experimental option for testing rollout DX at
Meta. If specified, this enables dynamic gating which matches `use memo
if(...)` directives.

#### Example usage
Input file
```js
// @dynamicGating:{"source":"myModule"}
export function MyComponent() {
  'use memo if(isEnabled)';
   return <div>...</div>;
}
```
Compiler output
```js
import {isEnabled} from 'myModule';
export const MyComponent = isEnabled()
  ? <optimized version>
  : <original version>;
```
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* __->__ #33149
* #33148