Replace Preconstruct with Crackle to build packages

[mrm007]

Preconstruct is out, Crackle is in.

This uses a snapshot version of Crackle with the latest unreleased changes. Will release once we're comfortable with the changes and I'll update Crackle in this PR.

I moved the generated metrics JSONs to packages/metrics/entireMetricsCollection/ and added an "exports" entry, as explained in https://github.com/seek-oss/crackle/pull/169 (using subpath patterns).

Technically, this is a major version for every package. Happy to discuss. Snapshot versions can be found here.

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Tested in Braid and SEEK internal packages.

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 1d8182d6d4eab3352b49011704795903a3a48c95

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

This PR includes changesets to release 4 packages

| Name | Type | | --------------------------- | ----- | | @capsizecss/vanilla-extract | Major | | @capsizecss/metrics | Major | | @capsizecss/unpack | Major | | @capsizecss/core | Major |

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