feat: rewrite to full node runner

[leekeh]

Description

Instead of using separate steps, we use one main script to improve readability.
The advantage is that we can directly manage the github artifacts, no longer needing to duct-tape a secondary action to our action.
The disadvantage is that we no longer can use other actions in our action, since the action is no longer composite.

This PR also improves management of the pnpm setup by requiring this to be done in the parent workflow. This is now documented.

Since a lot was rewritten, I took the time to clean up some things, mainly clean code stuff and some security.

Checklist

• I have verified any AI-generated code to be accurate, effective and aligned with the rest of the repository
• I have tested my changes with a sample run: link to run

Version Bump

• patch – bug fixes, documentation updates, minor improvements (default)
• minor – new features or notable changes (backwards compatible)
• major – breaking changes

[github-actions]

Caution

Accessibility issues were detected in this PR. Please fix them before merging.

The following routes have violations:

• index

[github-advanced-security]

You are seeing this message because GitHub Code Scanning has recently been set up for this repository, or this pull request contains the workflow file for the Code Scanning tool.

What Enabling Code Scanning Means:

• The 'Security' tab will display more code scanning analysis results (e.g., for the default branch).
• Depending on your configuration and choice of analysis tool, future pull requests will be annotated with code scanning analysis results.
• You will be able to see the analysis results for the pull request's branch on this overview once the scans have completed and the checks have passed.

For more information about GitHub Code Scanning, check out the documentation.