Make implicitly global parameter declarations local

[Saklad5]

These parameters were not explictly marked as local, which causes zsh to
make them global by default. This is presumably unintended, and pollutes
the environment, so they have been explicitly made local in the manner
already present in the file.

These parameters were found using the zsh option WARN_CREATE_GLOBAL.
There may be other implicit global parameters present, as it only
displays a warning when the relevant code is evaluated.

[Saklad5]

I'm working on the assumption that all implicit global variables are unintentional, such that simply making them local fixes the issue. If any of them are meant to be global, they should be explicitly global: while I very much doubt any of these fall into that category, I recommend briefly skimming the changes before merging.

I will continue to force-push additional fixes along the same lines if I encounter any until it is merged.