Step 15: the published benchmark #9

Design §8 step 15, from docs/design.md as the owner ruled it on 2026-09-25. The step's entry in design §8 records what each check printed when it passes; this issue tracks the work.

Step 15: the published benchmark. Every codec, every ruled baseline, every corpus, on the Linux runners of decision 20, and the README's tables generated from the results rather than written beside them.

Check: decision 10's method as decision 20 amends it, with each run recorded and the losses included.

Steps 3 to 8 are stdx issue 1, the decoder colibri waits on. Steps 9 to 14 complete version one.

Waits on: every step before it.