Feature accessability

[ScSteffen]

Proposed Changes

This PR updates the KiT-RT onboarding and documentation build docs based on a docs audit of the current repository state.

• Clarifies the CPU smoke-test prerequisites in README.md, doc/installation.rst, doc/getting_started.rst, and doc/tutorials/smoke_test.rst, including BLAS, LAPACK, VTK, OpenMP, initialized submodules, and Python 3.10+.
• Documents HIP/ROCm and local documentation build paths, including BUILD_HIP_HPC, BUILD_DOC, and the generated Sphinx HTML location.
• Fixes stale or misleading container and workflow references by replacing the ambiguous kitrt/test:latest Docker command with a local image build, aligning CharmKiT naming/links, and clarifying release-container wording.
• Expands doc/configFiles.rst with additional enum values from include/common/globalconstants.hpp, including output, entropy, optimizer, sampler, and WATERPHANTOM_1D values.
• Makes Sphinx builds warning-clean by excluding legacy API stub pages that reference removed or renamed classes, fixing title underline warnings, adding missing toolbox pages to the toctree, and including philosophy in the main toctree.
• Updates the CMake Sphinx invocation to pass the active Doxygen XML directory through KITRT_DOXYGEN_XML, so documentation builds work from arbitrary build directories instead of assuming ../build/docs/doxygen/xml.
• Assigns repository, Sphinx documentation, and runtime banner copyright to Steffen Schotthoefer, Pia Stammer, and Jonas Kusch.

Validation performed:

python3 -m py_compile doc/conf.py tools/check_smoke_output.py
sphinx-build -b html -W --keep-going doc /tmp/kitrt_sphinx_audit_after

The CPU smoke-test build was not rerun after these docs changes because this machine still lacks BLAS; CMake currently fails with Could NOT find BLAS, which is now called out in the docs.

Related Work

No linked issue. This follows the documentation audit for missing run instructions and stale or misleading docs.

PR Checklist

• I am submitting my contribution to the develop branch.
• My contribution is commented and uses the code style of the project (see .clang-format).
• I have added a test case that demonstrates my contribution, if necessary.
• I have added unit tests to protect my modules, if necessary.
• I have updated appropriate documentation (Tutorials, RTD Page), if necessary.