[DrunkOnJava]

Post-release docs for v0.12.1 (RELEASE.md, after publishing).

Every channel was checked from what was published, on 2026-11-02. Publish run 41543156775 was all green, and verification ran against Measure 41547212310 on the tag:

• crates.io: 0.12.1, recorded as published by run 41543156775 from eea153de (Trusted Publishing). Its page shows the 0.12.1 README.
• docs.rs: built 0.12.1.
• PyPI: the wheel installs 0.12.1 in a clean venv. On Core Interior, Einhoven and RE1 Architecture its IFC is line-equal to Measure's, with diagnostics equal as JSON.
• macOS arm64 archive: matches SHA256SUMS, and its attestation names release-binaries.yml at refs/tags/v0.12.1. Its IFC is line-equal to Measure's on the three models, with diagnostics byte-identical.
• Container image: its attestation verifies, and on linux/amd64 and linux/arm64 RE1 Architecture's IFC is line-equal to the archive's.
• Viewer: reports rvt-rs 0.12.1.

The release notes are now the CHANGELOG's [0.12.1] section plus the user-guide link, replacing GitHub's generated list.

Changes

• docs/install.md: publication status, the checks above, the platform table's range.
• docs/python.md: 0.12.1 is the current release.
• docs/status.md: v0.12.1 is the latest release, with its timing.
• ROADMAP.md: the 0.12.1 entry.

Testing

• N/A: docs only.

Audit-honesty checklist

• README / docs reflect the current state after this PR
• N/A: changelog fragment (the release's entry is in CHANGELOG.md)
• Commit messages describe what changed and why
• No emojis in code, docs, or commit messages
• No private paths, personal email addresses, or internal jargon in committed files

Breaking changes

None.