Add support for an --outDir CLI flag to astro build

[delucis]

Changes

• Passes the value of an --outDir CLI flag through to Astro config, so you can set the build output directory from the command line:

  astro build --outDir ./build

• I also took a look through the other config options that aren’t currently available as CLI flags. Only srcDir and publicDir felt like potential candidates, but those also both feel like fairly rare options, so chose to only add outDir as part of this PR.

Testing

There don’t seem to be any tests for astro build as far as I can tell? So not sure how to test exactly.

Docs

This will need documenting in the CLI reference docs.
/cc @withastro/maintainers-docs for feedback!

[changeset-bot]

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Latest commit: cad1013

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[github-actions]

This PR is blocked because it contains a minor changeset. A reviewer will merge this at the next release if approved.

[natemoo-re]

Works for me, thanks for the PR!

minor merge day

[ematipico]

@delucis have you tested this locally at least?

[delucis]

have you tested this locally at least?

Yup! I built and packed astro, installed the tarball in a local project, and ran astro build --outDir out. Behaved as expected.