docs: align consolidated solver workflow

phases/linear-static-3d-euler-beam/step2.md

@@ -11,16 +11,16 @@
 - `/AGENTS.md`
 - `/docs/SOLVER_AGENT_DESIGN.md`
 - `/docs/formulations/README.md`
-- `/docs/requirements/linear-static-3d-euler-beam.md`
-- `/docs/research/linear-static-3d-euler-beam-research.md`
-- `/docs/formulations/3d-isoparametric-euler-beam-formulation.md`
+- `/docs/linear-static-3d-euler-beam/requirements.md`
+- `/docs/linear-static-3d-euler-beam/research.md`
+- `/docs/linear-static-3d-euler-beam/formulation.md`
 - `/docs/superpowers/specs/2026-08-08-linear-static-3d-euler-beam-design.md`
 
 Step 0–1 산출물과 완료 summary를 확인하라.
 
 ## 작업
 
-기존 `docs/formulations/3d-isoparametric-euler-beam-formulation.md`를 승인된 V0 요구조건과
+기존 `docs/linear-static-3d-euler-beam/formulation.md`를 승인된 V0 요구조건과
 연구 근거에 맞춰 정렬하라. 기존 정식화의 정확한 수학적 의미를 유지해야 하며, 이
 step은 새 요소를 다시 설계하는 작업이 아니다.
 
@@ -43,11 +43,11 @@ step은 새 요소를 다시 설계하는 작업이 아니다.
 ## Acceptance Criteria
 
 ```powershell
-$path = 'docs/formulations/3d-isoparametric-euler-beam-formulation.md'
+$path = 'docs/linear-static-3d-euler-beam/formulation.md'
 $required = @(
   'status: `ready-for-numerical-review`',
-  'docs/requirements/linear-static-3d-euler-beam.md',
-  'docs/research/linear-static-3d-euler-beam-research.md',
+  'docs/linear-static-3d-euler-beam/requirements.md',
+  'docs/linear-static-3d-euler-beam/research.md',
   'theta_y=-',
   '2점 Gauss',
   'equilibrium end action',