Tidy the fyne CLI (in tools repo)

[andydotxyz]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

The CLI parameters were to be tidied as we migrate to new repo.
Placeholder issue here to prop release blocker state on the work.

How to reproduce

n/a

Screenshots

No response

Example code

n/a

Fyne version

v2.5.0-pre

Go compiler version

1.22

Operating system and version

all

Additional Information

No response

[Jacalz]

I believe that I managed to get all of the cleanups for the migration done. The points left to do are:

• Make cmd/fyne install command work more like go install tools#11
• Add a new API for Apps Browser to use tools#19

EDIT: The latter is likely not a blocker.