Add “Open with CodeSandbox” buttons to example project READMEs

[Ekwuno]

Changes

• What does this change?
  Just like in Edit docs with Codesandbox repos docs#1982. I have been using codesandbox a lot for my open-source contributions, and I think it's really cool. Astro doc contributors can work seamlessly, and I wanted to add it here as an option.

I noticed that in astro.new you have the option to open in codesandbox, but in the repos that are cloned, only the stackBlitz option exists.

• Be short and concise. Bullet points can help!
• Before/after screenshots can help as well.
• Don't forget a changeset! pnpm exec changeset

Testing

Docs

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⚠️ No Changeset found

Latest commit: a41d3c6

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[Ekwuno]

@sarah11918 just doing some more quality-of-life improvements 😅

[delucis]

Thanks @Ekwuno!

A lot of suggestions here 😅 But they’re basically all identical: remove a newline so the open buttons appear on the same line.

One README I noticed our existing link was wrong, so suggested fixing that in this PR too.

[Ekwuno]

Ah! Great catch @delucis I checked the deno example and saw they both open well. I added screenshots as well. Updated with all the suggestions now.

[delucis]

Thanks for making those changes @Ekwuno — LGTM!

[Ekwuno]

Oh! it pointed to basic example. before your suggestion. Just got it.. My bad 😅 @delucis