Diagram

```mermaid graph TB subgraph ML["Mathematica Layer"] QSF["QSF Core"]:::mathematica PG["Plot System"]:::mathematica DA["Data Analysis"]:::mathematica PI["Physics Interface"]:::mathematica end

subgraph CF["Core Framework"]
    subgraph WF["Wave Functions"]
        GS["Grid System"]:::wf
        MGS["Multigrid System"]:::wf
        ABS["Absorbers"]:::wf
        COMP["Computations"]:::wf
    end

    subgraph FP["Field Processing"]
        FPM["Main Field Processing"]:::field
        FPP["Field Parameters"]:::field
    end

    subgraph FX["Fluxes"]
        FC["Flux Calculations"]:::flux
        BH["Border Handling"]:::flux
        FM["Flux Masking"]:::flux
    end

    subgraph PC["Physics Components"]
        HAM["Hamiltonian"]:::physics
        PROP["Propagator"]:::physics
        POT["Potential"]:::physics
        COUP["Coupling"]:::physics
    end
end

subgraph BC["Basic Components"]
    CONF["Configuration"]:::basic
    CONST["Constants"]:::basic
    MATH["Math Operations"]:::basic
    MPI["MPI Integration"]:::basic
end

subgraph EX["External Dependencies"]
    FFTW["FFTW Library"]:::external
    MPIL["MPI Library"]:::external
end

%% Relationships
QSF --> PI
PI --> HAM
PI --> PROP
PG --> DA

GS --> FPM
MGS --> FPM
ABS --> COMP
COMP --> FPM

FPM --> FC
FPP --> FPM

FC --> BH
BH --> FM

HAM --> PROP
POT --> HAM
COUP --> HAM

CONF --> WF
CONST --> PC
MATH --> WF
MATH --> FP
MPI --> MPIL

FPM --> FFTW

%% Click Events
click CONF "https://github.com/QSF-physics/QSF/blob/main/include/basics/config.h"
click CONST "https://github.com/QSF-physics/QSF/blob/main/include/basics/constants.h"
click MATH "https://github.com/QSF-physics/QSF/blob/main/include/basics/math_basic.h"
click MPI "https://github.com/QSF-physics/QSF/blob/main/include/basics/mpi_logic.h"
click GS "https://github.com/QSF-physics/QSF/blob/main/include/wf/grid.h"
click MGS "https://github.com/QSF-physics/QSF/tree/main/include/wf/multigrid"
click ABS "https://github.com/QSF-physics/QSF/blob/main/include/wf/absorbers.h"
click COMP "https://github.com/QSF-physics/QSF/blob/main/include/wf/computations.h"
click FPM "https://github.com/QSF-physics/QSF/blob/main/include/field.h"
click FPP "https://github.com/QSF-physics/QSF/blob/main/include/field_p.h"
click FC "https://github.com/QSF-physics/QSF/blob/main/include/fluxes/flux.h"
click BH "https://github.com/QSF-physics/QSF/blob/main/include/fluxes/borders.h"
click FM "https://github.com/QSF-physics/QSF/blob/main/include/fluxes/flux_mask.h"
click HAM "https://github.com/QSF-physics/QSF/blob/main/include/hamiltonian.h"
click PROP "https://github.com/QSF-physics/QSF/blob/main/include/propagator.h"
click POT "https://github.com/QSF-physics/QSF/blob/main/include/potential.h"
click COUP "https://github.com/QSF-physics/QSF/blob/main/include/coupling.h"
click QSF "https://github.com/QSF-physics/QSF/blob/main/mathematica/QSF/Kernel/QSF.wl"
click PG "https://github.com/QSF-physics/QSF/tree/main/mathematica/PlotGrid"
click DA "https://github.com/QSF-physics/QSF/blob/main/mathematica/QSF/Kernel/DataAnalysis.wl"
click PI "https://github.com/QSF-physics/QSF/blob/main/mathematica/QSF/Kernel/Physics.wl"
click FFTW "https://github.com/QSF-physics/QSF/blob/main/cmake/FindFFTW.cmake"

%% Styles
classDef mathematica fill:#f9a,stroke:#333
classDef wf fill:#adf,stroke:#333
classDef field fill:#ada,stroke:#333
classDef flux fill:#dad,stroke:#333
classDef physics fill:#fda,stroke:#333
classDef basic fill:#ddd,stroke:#333
classDef external fill:#ccc,stroke:#333

%% Legend
subgraph Legend
    L1["Mathematica Components"]:::mathematica
    L2["Wave Function Components"]:::wf
    L3["Field Processing"]:::field
    L4["Flux Components"]:::flux
    L5["Physics Components"]:::physics
    L6["Basic Components"]:::basic
    L7["External Dependencies"]:::external
end

```

Testing

Define TEST_MULTIGRID_MASK C preprocessor flag to output region=1 grid/grid slice masks.