FDTD | Feature | Include IA infrastructure, Added XDMF/HDF5 movie outputs and frequency-domain volumetric slices

[adrianarce-elemwave]

Summary

Introduces an isolated, AI-ready development container and integrates the new observation-output pipeline.

What changed

• Adds reproducible quality and dev Docker targets with compilers, HDF5, MPI, ParaView, Python tooling, and OpenCode support.
• Configures Dev Container mounts, environment checks, VS Code debugging, CMake presets, and Fortran-focused OpenCode skills.
• Adds the new output module behind SEMBA_FDTD_ENABLE_OUTPUT_MODULE.
• Integrates output initialisation, updates, flushing, and shutdown into the solver time-stepping lifecycle.
• Adds XDMF/HDF5 movie outputs and frequency-domain volumetric slices for electric, magnetic, and current-density fields.
• Adds unit-test infrastructure and example input data for movie and frequency-slice probes.
• Extends CI to build both legacy and new output-module configurations.

Validation

• CI compiles the output module across GCC/Intel, MPI, MTLN, and precision configurations.
• Python integration tests remain enabled for the legacy output path only.
• Adds dedicated Fortran tests for output handling, VTK API, XDMF API, volumetric utilities, and test assertions.

Notes for reviewers

• The new output pipeline is enabled by default with SEMBA_FDTD_ENABLE_OUTPUT_MODULE=ON. Next follow ups will remove legacy implementation alongside this flag
• The existing observation implementation remains available by disabling that option.
• This PR combines development-infrastructure changes with output-module integration.