docs(fundamentals): display icons in 'frequent app functions' page

[spliffone]

fixes #1444

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[gemini-code-assist]

Code Review

This pull request adds the necessary configuration to display icons in the documentation, which involves including the Siemens Element icon CSS and adding some helper classes. The changes are generally good, but I've identified an opportunity to improve the robustness of how the icon CSS file path is resolved in plugin.py. My feedback includes a specific suggestion to make the path resolution more dynamic and less dependent on the execution environment's current working directory.

[gemini-code-assist]

The hardcoded relative path './node_modules/...' is brittle because it relies on the current working directory. While mkdocs typically changes the CWD to the project's root directory, this can be unreliable in different execution environments or with different mkdocs invocation methods.

For better robustness and consistency with other parts of this project (e.g., index.mjs), I recommend dynamically locating the node_modules directory by traversing up the file system. This makes the plugin more resilient.

You could replace the current line with logic like this:

# Find node_modules directory by traversing up from the current working directory
path = os.getcwd()
nm_path = None
for _ in range(10): # Limit search depth to 10 levels
    if os.path.isdir(os.path.join(path, 'node_modules')):
        nm_path = os.path.join(path, 'node_modules')
        break
    parent = os.path.dirname(path)
    if parent == path: # Reached root
        break
    path = parent

if not nm_path:
    raise FileNotFoundError("Could not find 'node_modules' directory.")

icon_css_src_dir = os.path.join(nm_path, '@siemens/element-icons/dist/style/')
files.append(File('siemens-element-icons.min.css', icon_css_src_dir, config.get('site_dir'), config.get('use_directory_urls')))

[github-actions]

Documentation.
Examples.
Playwright report.

Coverage Reports:

• element-ng
• element-translate-ng

[github-actions]

[spike-rabbit]

Instead of loading it for every file, please just load it into the affected one.

We already have the style symlinked into the docs.
So just adding <link rel="stylesheet" href="_src/siemens-element-icons.min.css" /> should be enough.

When we finally have the live-preview as a web-component, we can maybe start adding this globally.