feat(cli): allow to specify sourcemap mode via --sourcemap build's option

[wreckah]

Description

Currently there are no ways to set build.sourcemap to hidden via CLI. But it may be useful to set it on different environments without customization of Vite config, for example in CI:

# On staging:
npm run build -- --sourcemap
# On production:
npm run build -- --sourcemap hidden

Additional context

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[sapphi-red]

The code and behavior looks good to me!

Would you update this part, too?

vite/docs/guide/cli.md

Line 57 in f12a1ab

| `--sourcemap` | Output source maps for build (default: `false`) (`boolean`) |

[wreckah]

Would you update this part, too?

vite/docs/guide/cli.md

Line 57 in f12a1ab

| `--sourcemap` | Output source maps for build (default: `false`) (`boolean`) |

@sapphi-red sure d981c0c

[sapphi-red]

Thank you!

[ivana-helvin]

Hi I don't know how to add this to my vite 4.1.4, please can you help?

[bluwy]

We will only ship this in Vite 4.2 when it's released.

[patak-dev]

@ivana-helvin you can test it now at vite@4.2.0-beta.0 (stable release will probably take ~10-15 days)