Release 0.9.4

[github-actions]

What's Changed

• feat: validate attestation gateway even on disabled by @paolodamico in feat: validate attestation gateway even on disabled #213

Full Changelog: 0.9.3...0.9.4

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Note

Medium Risk
Touches attestation/security-related behavior; deployments with the gateway disabled may see new validation failures if config or tokens were previously unchecked.

Overview
Release 0.9.4 bumps the workspace and crate versions from 0.9.3 to 0.9.4 (including Cargo.lock) and documents the release in CHANGELOG.md.

The functional change in this release is attestation gateway validation when the gateway is disabled (from #213): the service still validates attestation gateway configuration/tokens rather than skipping checks entirely when the feature is off.

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