DN-269: The Synthesis -- Consolidation of the Dwarf Spheroidal Arc (CDN-256-268)

Synthesises the 13-note dSph arc (CDN-256-268) into a unified status document covering the full GCFT coupling landscape from galaxy clusters to ultrafaint dwarfs. Cross-checks the CDN-268 zero-DM prediction for Fornax against Walker+2009 (GCFT M_dyn=1.7e8 matches 1.6e8 without a halo) and Leo I against Lokas 2009 (GCFT 3.2e7 compatible with 4e7). Updates the theory-debt ledger to 9/12 resolved, with three open: D1 (v_r-linearity), D11 (derive why nu(x) is the McGaugh function), and new D12 (explain the 100x DM reduction mechanism from coherence-field microphysics). Catalogues seven falsifiable predictions including zero-DM halos for Fornax and Leo I, 100x lighter dSph halos than LCDM, and exact nu(x) at galaxy scale. The dSph arc concludes: the coherence field is MOND at galaxy scale, coexists with dark matter at dwarf scale, and needs a hundred times less of it than LCDM.