Feat/download function

[JerryVincent]

Modified download feature.

[scheidtdav]

Great progress so far!
I noticed a couple of small things in the code itself, please address those.

A couple more things to consider:

1. I think all the new stuff we add should be in german and english straight away. For that reason you should add the translation function to your newly added strings
2. May I recommend to refactor the action a little bit: Move the individual file formats into their own functions to prevent getting spaghetti code and increase reusability. E.g. one function for csv, one for json, etc. and then just call those in the action. Makes it way more readable :-)
3. Why do I need to click the "download" button after the preparation is done? Can't this just start automatically? Would make it more user friendly in my opinion. Also can we add a note to not close the modal during the process or otherwise the download will be interrupted?
4. If you are interested in fiddling around with performance improvements, we can have a chat about parallelizing some promises, specifically for accessing the measurements. A couple of lines including Promise.all could help speed up things for the user. Just let me know.

[scheidtdav]

Still some ESLint warnings as far as I can tell.
I left two small things I found as well.

You could further increase the readability of your action by taking out the functions that generate each individual file format to a different place in the code. This way it is taken out from the reading flow.
One option would be to move it to a new file like file-exports.ts in the utils folder.