Improve Astro JSX rendering

[bluwy]

Changes

Fixes #10158

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This fix requires some context, so here it is 😄:

When rendering JSX nodes, there's currently a problem where it can call renderComponentToString to render React/Vue/MDX component from JSX nodes, but it can also render JSX nodes again if it hits the astro:jsx renderer (for MDX). Creating a loop.

Before

The solution to this problem is using "Skips" to make sure this order is ran (Worst case):

1. Try to render JSX nodes.
2. If fail, try to render components with React/Vue/MDX renderers.
3. Detected MDX, try to render its JSX nodes again.
4. Try to render components with React/Vue/MDX renderers.
5. Detected MDX, try to render its JSX nodes again.
6. Try to render JSX nodes again.
7. Finished. Returns rendered string or error.

(I don't know why no4 and no5 repeated. Perhaps a typo in the logic?)

After

We use a single Symbol only to check if it had tried to render with React/Vue/MDX renderers. New order (Worst case):

1. Try to render components with React/Vue/MDX renderers.
2. Detected MDX, try to render its JSX nodes.
3. Finished. Returns rendered string or error.

This refactor allows us to simplify the skips logic, and remove the console filter as we no longer unconditionally render vnode.type. renderComponentToString will check for it first.

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Testing

Existing tests should pass. Also tested the repro manually from #10158 (didn't add test because Svelte 5 is still experimental and hard to setup test). Also tested repro from #4894.

Docs

n/a. bug fix.

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[bluwy]

We now only try to render the head if this component is a page and is non-partial. Otherwise there's chance we could render a component but not use it (with how the new renderJSX flow works)

[bluwy]

!bench render

EDIT: It doesn't look like there's much gain

[ematipico]

!bench render

EDIT: It doesn't look like there's much gain

Performance-wise, maybe not, but memory-wise, maybe yes. We don't construct a Skip class anymore, which is definitely some good nonetheless.

[ematipico]

Less code is the best code! 💪

[Princesseuh]

Looks fine to me!