Align shared governance and documentation baseline

[hindermath]

Summary

• align TinyPl0 guidance files with the shared cross-repo governance baseline
• formalize DE-first/EN-second CEFR-B2, .EN.md sidecars, text-first accessibility, and DocFX follow-up review rules in the Pflichtenhefte
• add the required final block, refresh the statistics ledger, and sync the IDE version metadata for the branch update

Testing

• not run (documentation/governance change only)