docs: reset mitc4 formulation baseline

docs/README.md

@@ -80,11 +80,10 @@ Before creating Phase 1 implementation steps:
 - Use `../references/` as the accepted reference artifact folder.
 - Use Abaqus `.inp` files plus solved `*_displacements.csv` files as the first automated displacement reference format.
 - Keep a compatibility note when a stored Abaqus reference input contains features outside the current Phase 1 parser subset.
-- Finalize the MITC4 transverse shear tying-point equations.
-- Finalize the MITC4 local shell basis algorithm.
-- Finalize the default artificial drilling stiffness scale.
-- Decide whether Phase 1 outputs only `U` and `RF`, or also `S`, `E`, and `SF`.
-- Decide the build system, with CMake as the recommended default unless project constraints say otherwise.
+- Use the current `MITC4_FORMULATION.md` as the Phase 1 MITC4 gate before implementing or reviewing element stiffness.
+- Treat `U` and `RF` as the mandatory Phase 1 outputs; `S`, `E`, and `SF` require a later recovery-location decision.
+- Treat CMake/CTest as the Phase 1 build and test harness unless a later ADR changes it.
+- Before resuming Phase 1 implementation, re-plan against the revised MITC4 formulation and the `quad_02` S4 reference compatibility note.
 
 ## Documentation Change Rules
 - Keep changes narrow and update every affected document.