More integration README fixes

[delucis]

Changes

More tweaks to README formatting to accompany withastro/docs#954

Key things:

• Update the homepage field in package.json to point to the new docs pages!
• Add standard content for troubleshooting & changelog sections of READMEs
• Remove empty Examples sections from READMEs
• Don’t use <br> as they look out of place in the styled context of the docs
• Use code backticks for filenames
• Make sure code blocks all have a language (sh, js, etc.)

Testing

n/a

Docs

All docs, all the time ✨

[changeset-bot]

🦋 Changeset detected

Latest commit: 9bc7548

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 22 packages

Name	Type
@astrojs/cloudflare	Patch
@astrojs/deno	Patch
@astrojs/image	Patch
@astrojs/mdx	Patch
@astrojs/netlify	Patch
@astrojs/node	Patch
@astrojs/partytown	Patch
@astrojs/preact	Patch
@astrojs/prefetch	Patch
@astrojs/react	Patch
@astrojs/sitemap	Patch
@astrojs/solid-js	Patch
@astrojs/svelte	Patch
@astrojs/tailwind	Patch
@astrojs/vercel	Patch
@astrojs/vue	Patch
@e2e/preact-component	Patch
@e2e/react-component	Patch
@e2e/solid-component	Patch
@e2e/svelte-component	Patch
@e2e/ts-resolution	Patch
@e2e/e2e-tailwindcss	Patch

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[sarah11918]

It all LGTM, @delucis !

[tony-sull]

This looks great! Very excited to see these pages right on the docs site! Looks good to me once the docs pages are merged in 🚀

Added one tiny note related to keeping the use of sh vs shell consistent, feel free to ignore as they should be aliases in the markdown parser anyway 😄