Only enable optimise sockets button when it will do something

[vaisest]

Fixes #moxaj:

Description of the problem being solved:

This adds an enabled function to the optimise button. This should prevent it from lighting up when it won't do anything

Steps taken to verify a working solution:

• Doesn't break with split groups
• Doesn't light up when count is over socket limit
• Lights up when necessary

Link to a build that showcases this PR:

Before screenshot:

After screenshot: