Resolve Shadowed public Members

[LeStarch]

F´ Version
Affected Component

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Feature Description

With the merge of #2482, shadowed public members were renamed with the a_ prefix for "argument". We should review these uses and decide how to proceed.

Rationale

Public members are discouraged but have a purpose. a_ is not a long-term solution either, but effectively resolves the issue and makes it easy to find these problems for discussion.

[JohanBertrand]

For reference, we had some discussions about this point in a FPP issue: nasa/fpp#326