Remove unnecessary config from root dir

• create new folder .build-scripts and move tweak_build.sh into it
• adjust runner cmd in package.json => npm run tweak:build

How to test (on your local)

• checkout the branch
• npm run build (creates a dist folder in the root dir)
• npm run tweak:build (patches the quasar build step)
• take a look at the dist folder in the root dir; it should now consist of 2 files: tido.js and index.html

note: the tweak_build-script is also called during ci, so the only possibility to test it before the merge is done, would / could be to make a dummy commit and push it.

thereafter you can take a look at the pipeline (gitlab) and watch the job succeed.

=> please revert your changes (dummy commit)