make @metamask/vault-decryptor site publishable

[Unik0rnMaggie]

Make @metamask/vault-decryptor site publishable.

Part of the larger effort to remove live requests from E2E tests: MMQA-273

JIRA task: MMQA-669

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Note

Prepares the package for public npm publishing.

• Remove private: true from package.json
• Add files whitelist to publish only index.html and bundle.js
• Add publishConfig with access: public and npm registry URL
• Minor packageManager formatting adjustment

^{Written by Cursor Bugbot for commit 47a36a1. This will update automatically on new commits. Configure here.}

[cursor]

Main entry point file excluded from published package

Medium Severity

The files array specifies only index.html and bundle.js to be included in the published package, but the main field still references index.js, which won't be published. When consumers try to require('@metamask/vault-decryptor'), npm will attempt to load index.js and fail because that file doesn't exist in the published package. The main field should either be removed, updated to point to an included file, or index.js (and its dependencies in lib/ and app/) should be added to files.