Add note about having to run astro build before astro preview

[hirasso]

Description (required)

Yesterday I got bitten by not having completely understood that astro preview doesn't automatically build the project. This PR adds a caution box to save others some time:

Related issues & labels (optional)

• astro preview fails silently with missing dist folder astro#9297
• Suggested label: add new content

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Name	Status	Preview	Updated (UTC)
docs	✅ Ready (Inspect)	Visit Preview	Dec 12, 2023 11:07am

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[sarah11918]

Thank you for this contribution, @hirasso ! We appreciate you taking the time to add some helpful content for the next person! 🙌

I have edited the format of your content to be more in line with the rest of our docs. We rarely add notes, which are for tangential information, and almost never add cautions which are for truly alarming/security issues to watch out for.

We prefer to incorporate important content into the main text itself, instead of new content being "oh, and another thing!" or "Oh, and note this!" This makes for a better reading experience, and if it's important content, it should be said right the first time.

I've reviewed our documentation both on astro build and astro preview and added a bit of extra context right in the description to show that preview is meant to be used in conjunction with build. Rather than a scary warning message, I have linked the two together.

I do think this is helpful extra context to have, and we are happy you contributed it! Welcome to Team Docs! 🥳

[hirasso]

Hi Sarah! Thanks for your help with this. Appreciate it!

After reading through the updated text, I must confess that I would still not understand that astro preview doesn't run astro build automatically 😅. It's probably absolutely clear to you, but for an outsider with no concept of Astro's internals it would be helpful to at least add a little something mentioning this fact.

[hirasso]

As an aside note: very interesting to read your thoughts about when to use a note/caution. I just plain love the Astro docs! ❤️

[sarah11918]

Hi @hirasso, See what you think now! I tried to add a little bit more context in both the opening line and the next paragraph.

[hirasso]

@sarah11918 now it's much more clear! Ready to be merged I'd say 😊