Verify published JSR/GHCR release identity without self-referential image docs

[superWorldSavior]

Context

The immutable @casys/mcp-modelica@0.6.1 package still says that its matching image is forthcoming and presents the prior image digest, while the repository README was corrected only after the release tag. A published package must not carry time-sensitive pre-publication wording.

Acceptance criteria

• The README that is shipped in each future JSR package uses temporally neutral deployment wording: it contains no forthcoming-release claim and no historical-image stand-in presented as that package release.
• The documentation does not require embedding the digest of the same release image before that image is built. Instead, it directs deployment evidence to resolve and record the immutable GHCR index digest only after the paired image publication has succeeded.
• A post-publication verification, sequenced after both publication surfaces are available, proves the exact JSR package version is present and the GHCR release image resolves to an immutable OCI index.
• That verification proves the JSR package version, GHCR image version label, and OCI revision label agree with the release tag and its exact commit; it checks every published native platform rather than a mutable tag alone.
• The verification reads the published JSR README or package metadata so a source-checkout-only assertion cannot mask stale immutable package documentation.
• Tests cover the neutral README template and the post-publication verifier parsing success and mismatch fixtures. A release is not announced as verified when this post-publication check fails.

Scope

Likely touch points: README.md, CHANGELOG.md, release-version metadata, a bounded release-verification script, the two publish workflows, and focused release-input/verifier tests.

Out of scope

• Changes to Modelica kits, solver/runtime qualification, run evidence, MCP schemas, authentication, or tool behaviour.
• Requiring a pre-build self-reference to a digest that does not yet exist.

Version impact

Documentation and release-verification change; ship in the next intentional patch release with its paired image publication.