# Step 8: Shell Load Validation

## 담당 역할과 필수 스킬

- 담당 역할: `implementation-agent`
- 필수 스킬: `harness`, `fesa-cpp-msvc-tdd`

## 읽어야 할 파일

- `/.agents/skills/harness/SKILL.md`, `/.codex/skills/fesa-cpp-msvc-tdd/SKILL.md`
- `/AGENTS.md`, `/docs/PRD.md`, `/docs/ARCHITECTURE.md`, `/docs/ADR.md`
- `/docs/HARNESS.md`, `/docs/HARNESS_WORKFLOW.md`, `/.codex/hooks.json`
- `/docs/implementation-plans/linear-static-mitc4-shell-implementation-plan.md`
- `/docs/requirements/linear-static-mitc4-shell.md` Requirements 017-020/028
- `/docs/research/linear-static-mitc4-shell-research.md`
- `/docs/formulations/mitc4-shell-formulation.md` Sections 8, 13
- `/docs/numerical-reviews/linear-static-mitc4-shell-review.md`
- `/docs/io-definitions/linear-static-mitc4-shell-io.md` Sections 4.2-4.3
- `/docs/reference-models/linear-static-mitc4-shell-reference-models.md`
- phase indexes, `step8.md`, completed Steps 2/7 paths and summaries
- `/include/fesa/assembly/load_assembler.hpp`
- `/src/fesa/assembly/load_assembler.cpp`
- `/tests/unit/assembly/load_assembler_test.cpp`
- `/tests/unit/constraints/essential_constraints_test.cpp`

## 작업

1. `MITC4-LOAD-001..004`를 먼저 작성한다.
2. Existing global six-DOF full-space CLOAD assembly와 constraint partition을 재사용한다.
3. Node별 global force/moment를 stable source order로 먼저 aggregate한다.
4. Moment가 exact zero면 별도 나눗셈 없이 accept한다. Nonzero면 approved director로
   `rho_M=abs(dot(d,M))/norm(M)`을 계산해 `rho_M<=1e-12`만 accept한다.
5. Rejected moment는 `unsupported-drilling-load`로 RHS/substitution/drill stabilization
   이전에 실패해야 한다. Existing `Ff-Kfc*dc`와 factorization-before-load를 보존한다.

## Acceptance Criteria

```powershell
$requiredBuildPaths=@("C:/git/googletest","C:/Program Files (x86)/Intel/oneAPI/mkl/2026.1/lib/cmake/mkl","C:/Program Files (x86)/Intel/oneAPI/tbb/2023.1/lib/cmake/tbb","C:/Program Files/HDF_Group/HDF5/2.1.1/cmake")
foreach($p in $requiredBuildPaths){if(-not(Test-Path -LiteralPath $p)){throw "Missing $p"}}
cmake --fresh -S . -B .harness/build -G "Visual Studio 18 2026" -A x64 `
  "-DFESA_GTEST_SOURCE_DIR=C:/git/googletest" `
  "-DMKL_DIR=C:/Program Files (x86)/Intel/oneAPI/mkl/2026.1/lib/cmake/mkl" `
  "-DTBB_DIR=C:/Program Files (x86)/Intel/oneAPI/tbb/2023.1/lib/cmake/tbb" `
  "-DHDF5_DIR=C:/Program Files/HDF_Group/HDF5/2.1.1/cmake"
cmake --build .harness/build --config Debug --target fesa_unit_tests
ctest --test-dir .harness/build -C Debug -R "LoadAssembly|EssentialConstraints" --output-on-failure
```

Moment projection/diagnostic RED 뒤 minimal GREEN. 이후:

```powershell
cmake --build .harness/build --config Debug --target fesa_unit_tests
ctest --test-dir .harness/build -C Debug -R "LoadAssembly|EssentialConstraints|InpDomainMapping" --output-on-failure
cmake --build .harness/build --config Debug
ctest --test-dir .harness/build -C Debug --show-only=json-v1
ctest --test-dir .harness/build -C Debug --output-on-failure
```

## 검증 및 상태 갱신

현재 Step의 RED/GREEN/VERIFY evidence와 exact threshold를 summary에 기록한다.

## 금지사항

- DLOAD/equivalent/follower/distributed load를 구현하지 마라.
- Numerical drilling을 load channel로 사용하지 마라.
- Factorization/load lifecycle을 재정렬하지 마라.
- 직접 commit/hook 실행 또는 reference/upstream 변경을 하지 마라.