[mcp] Prompt improvements for smarter tool composition (#33108)

Our runtime results are still bogus, but so far this tweak let's the llm
use the tools a little more intelligently.

example:
---

```js
import React from 'react';

function App() {
  const [count, setCount] = React.useState(0);
  const [data, setData] = React.useState([]);

  React.useEffect(() => {
    const processData = () => {
      console.log("Processing data...");
      const newData = [];
      for (let i = 0; i < 1000000000; i++) {
        newData.push({ id: i, value: Math.random() * count });
      }
      return newData;
    };

    const processedData = processData();
    setData(processedData);
  }, [count]);

  return (
    <div>
      <p>Count: {count}</p>
      <p>Data Length: {data.length}</p>
      <ul>
        {data.slice(0, 5).map((item) => (
          <li key={item.id}>Item {item.id}: {item.value.toFixed(2)}</li>
        ))}
      </ul>
    </div>
  );
};
```
why is this component slow? use the react tools to figure this out.

> I'll analyze why this component is slow using the React tools. Let's
first evaluate the performance of the original code.
>
[review-react-runtime ...]
>
> The performance measurement tool timed out, which is a strong
indication of just how severe the performance issue is in this
component. Let's now try to compile the code to see if React Compiler
can identify any issues:
>
[compile...]
>
> Now I understand the issue. Let's analyze why this component > is
extremely slow:
> Main Performance Issues:
>
> Massive Data Processing: The component is trying to create an array
with a billion (1,000,000,000) objects in the processData function. This
is an enormous amount of data that will:
>
> Consume massive amounts of memory
> Take an extremely long time to process
> Likely crash the browser
>
>
> Unnecessary Recalculation: The effect depends on [count], meaning
every time the count changes, it will reprocess this enormous dataset.
> Inefficient Data Handling: Even though only 5 items are displayed, the
component processes a billion items.
>
> Let's fix these issues:
>
[compile...]
>
> Now let's check if our modified code performs better:
>
[review-react-runtime...]
>
> Excellent! The performance has dramatically improved. Now let's check
the React documentation to make sure we're following the best practices:
>
[query-react-dev-docs...]

(hit the maximum length conversation limit because i'm on a free plan)