[JoKeyser]

Thanks a lot for maintaining this template, it helps me getting started much easier.
While trying it out I hit a crash when building the docs, so here is a small fix (probably with a fairly indirect root cause behind it).

When trying to build the docs, it segfaults while reading coder/ExampleVisualStim. I saw this with PsychoPy 2026.2.4, pyglet 1.5.27, Sphinx 8.1.3 and Python 3.10, both on Linux with a display and on macos-latest. (Used command: sphinx-build docs_src docs -b dirhtml).

With this PR, docs_src/conf.py now mocks psychopy.tools.gltools.
With it, psychopy.visual gets imported and documented without segfault.

My best guess at the cause: Sphinx imports psychopy.visual to document the plugin, which imports psychopy.tools.gltools, which queries OpenGL at import time. pyglet skips creating its hidden window when sphinx is in sys.modules, so there is no OpenGL context and the query crashes in native code. The try/except around it can't catch that. I also tried autodoc_mock_imports, but it doesn't help: the crashing import happens in sphinx.pycode, outside autodoc's mock context.

To check it yourself:

• Built docs from my fork: https://jokeyser.github.io/psychopy-plugin-template/
• Docs workflow run on macos-latest, succeeded: https://github.com/JoKeyser/psychopy-plugin-template/actions/runs/37352246022
• Locally: pip install -e .[docs] && sphinx-build docs_src docs -b dirhtml

What I tested: The build succeeds on Linux laptop (Python 3.10), and the full docs workflow succeeds on macos-latest.