[compiler] Improve impurity/ref tracking

[josephsavona]

note: This implements the idea discussed in https://github.com/reactwg/react/discussions/389#discussioncomment-14252280

Currently we create Impure effects for impure functions like Date.now() or Math.random(), and then throw if the effect is reachable during render. However, impurity is a property of the resulting value: if the value isn't accessed during render then it's okay: maybe you're console-logging the time while debugging (fine), or storing the impure value into a ref and only accessing it in an effect or event handler (totally ok).

This PR updates to validate that impure values are not transitively consumed during render, building on the Render effect. The validation currently uses an algorithm very similar to that of InferReactivePlaces - building a set of known impure values, starting with Impure effects as the sources and then flowing outward via data flow and mutations. If a transitively impure value reaches a Render effect, it's an error. We record both the source of the impure value and where it gets rendered to make it easier to understand and fix errors:

Error: Cannot access impure value during render

Calling an impure function can produce unstable results that update unpredictably when the component happens to re-render. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent).

error.invalid-impure-functions-in-render-via-render-helper.ts:10:25
   8 |     const array = makeArray(now);
   9 |     const hasDate = identity(array);
> 10 |     return <Bar hasDate={hasDate} />;
     |                          ^^^^^^^ Cannot access impure value during render
  11 |   };
  12 |   return <Foo renderItem={renderItem} />;
  13 | }

error.invalid-impure-functions-in-render-via-render-helper.ts:6:14
  4 |
  5 | function Component() {
> 6 |   const now = Date.now();
    |               ^^^^^^^^^^ `Date.now` is an impure function.
  7 |   const renderItem = () => {
  8 |     const array = makeArray(now);
  9 |     const hasDate = identity(array);

Impure values are allowed to flow into refs, meaning that we now allow useRef(Date.now()) or useRef(localFunctionThatReturnsMathDotRandom()) which would have errored previously. The next PR reuses this improved impurity tracking to validate ref access in render as well.

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• [compiler] Validate ref reads in render via improved impure value validation #35450
• -> [compiler] Improve impurity/ref tracking #35298