Merge development branch with conflict resolution

Resolved conflicts:
- Renamed workflow files from .yml to .yaml (standard naming)
- Removed pdoc workflow (docs now use Sphinx)
- Removed obsolete docs/user/Installation.qmd (superseded by restructured docs)
- Removed docs/_quarto.yaml (Quarto not used for main docs)
- Merged environment.yaml with pytest-mpi and pygmsh from RC

Changes from development:
- Container configuration updates
- Workflow file renames for consistency
- Solver improvements for boundary conditions
- New test for Poisson natural BCs

Underworld development team with AI support from Claude Code

Author: lmoresi

.github/.devcontainer/DOCKERFILE_GHCS

@@ -4,8 +4,8 @@ RUN conda install -n base -c conda-forge mamba
 
 # Here we can install all the dependencies using mamba (as we do in the test scripts)
 
-COPY .devcontainer/uw_environment.yml  /tmp/conda-tmp/
-RUN  mamba env update -n base --file /tmp/conda-tmp/uw_environment.yml 
+COPY .devcontainer/uw_environment.yaml  /tmp/conda-tmp/
+RUN  mamba env update -n base --file /tmp/conda-tmp/uw_environment.yaml 
 
 # Add other dependencies that can't be installed correctly.
 

.github/.devcontainer/uw_environment.yaml

@@ -0,0 +1 @@
+../../environment.yaml

.github/.devcontainer/uw_environment.yml

@@ -23,7 +23,7 @@ jobs:
       - name: Install Conda environment with Micromamba
         uses: mamba-org/setup-micromamba@v2
         with:
-          environment-file: ./environment.yml
+          environment-file: ./environment.yaml
           cache-downloads: true
           cache-environment: true
 

.github/workflows/build_deploy_pdoc.yml

@@ -34,7 +34,7 @@ jobs:
     - name: Cache book files
       uses: actions/cache@v1
       env:
-        # Increase this value to reset cache if etc/example-environment.yml has not changed
+        # Increase this value to reset cache if etc/example-environment.yaml has not changed
         CACHE_NUMBER: 0
       with:
         path: |