The Down-Quark Phase Resolved by the Shared-Multiplet Dimensional Rule (T270): One Method for Both Quark Sectors Gives deltaD = 4/27 and deltaU = 2/27, Superseding T155v2 Theorem 2, with the 4/3 Correction Equal to Both the SU (3) Casimir and Twice the Koide Ratio | Synapse