Suppress curl and floating number conversion

[yubiuser]

What does this PR aim to accomplish?:

During rare circumstances (FTL restart and PADD data request) curl could fail and output error text in the unused x/y-offset margins. As this area is not cleared by default (to avoid flickering) the error text remains.

This PR removes the -S, --show-error flag from curl calls to prevent any error output.

Additionally, it guards floating number conversions incase the input is empty.

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[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[github-actions]

Conflicts have been resolved.

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[github-actions]

Conflicts have been resolved.

[rdwebdesign]

The issue is still happening.

There are more errors that need to be addressed

[yubiuser]

I pushed a commit that should guard all floating number conversions. Please test @rdwebdesign

[rdwebdesign]

Tested after your new commit, but it still shows the same invalid number error. See my comments in MM.

[yubiuser]

Setting to draft, maybe most won't be needed when we reduce the number of API calls

[yubiuser]

Superseded by #399