feat!: Automatically categorize changelog entries with conventional commit type

[Mrtenz]

This enables the autoCategorize option on auto-changelog, which automatically categorizes entries based on the conventional commit type.

Closes #159.

Breaking changes

• The generated changelog is now different for commits with conventional commit types.

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Note

Medium Risk
Changes release/changelog generation behavior (including a breaking output format change), which could affect downstream tooling or expectations during publishing, but does not touch runtime product logic or security-sensitive code.

Overview
Enables autoCategorize when calling @metamask/auto-changelog during updatePackageChangelog, causing generated changelog entries to be grouped by conventional commit type.

Updates unit tests and the built dist/index.js bundle to assert/pass the new autoCategorize: true option through to updateChangelog.

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[mcmire]

Makes sense!