The F3 record and its harness crate (tools/attack/f3-cache: the extracted chain,
the exhaustive closure search, the pebbling cross-check, the store-set DP and
brute force, the two planted broken chains). The optimal-placement observation
(3.17 blocks per read at f=1/8, 16.0 at f=1/64) noted against funding.md B2.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>