Bug: Don't allow the steam path to be the same as install path for agent smith itself.

[jreed1701]

[Kableka]

More specifically it would be good to have it default to a ".../steam" if the install path leads to the same root directory as Agent Smith.

Examples:
user input -> "C:\AgentSmith"
Appended correction -> "C:\AgentSmith\steam"

user input -> "C:\AgentSmith\Donkey"
No appending needed because they would be installing it into the Donkey Folder

user input -> "C:\AgentSmith\platform\steam"
No appending needed for same reasons above. (platform subdirectory an option for if Epic or some other launcher get added down the line)

[Kableka]

github gui is too greedy with its button selection, this should still be open