Proper auto-dist mechanism

• Reconfigure vite: "outDir": "tmp.vite-autodelete.output" because it recklessly removes and recreates the outDir.
• Add post-build step to move the generated files and rmdir the outDir.
• Add an auto-dist script similar to pre2gfm
  • Or maybe for this project it might suffice to use a dist/.npmignore distinct from dist/.gitignore and add a note to upgrade if they evolve an overlap.
  • GitLab pages must be explicitly enabled in the CI config. Expected output URL