[Feature] Captive Portal: Config Page

[nullstalgia]

Pre-submission checklist

• I checked that there is no other Feature Request describing my wish.
• I checked that this feature is, in fact, not supported.
• I accept that this issue may be closed if any of the above are found to be untrue.

What should be possible that currently is not?

After #410 is enacted, there will need to be an alternate page for when accessing the Portal after setup is complete.

All options during setup should be available.

All options should be on one or two shared pages, no 1->2->3 flow.

Extra options should be shown, such as listing or removing saved networks.

Other remarks

No response