Reorganize settings navigation and tab customization

[codebymini]

Summary

• Move tab customization into the settings navigation flow instead of presenting it as a separate sheet
  simplify the tabs screen by removing modal-specific state and using standard dismiss/navigation behavior
• Rename the settings entry from Tab Settings to Tabs
• Reorganize SettingsMenuView.swift so display-related items are grouped under a new Display Settings section
• Move Information Display into the display section while keeping Remote under app settings when Nightscout is configured

Details

• SettingsMenuView.swift now routes Tabs through the existing settings navigation stack and rebuilds tabs after applying changes
• TabCustomizationModal.swift no longer depends on an external presentation binding and is structured like a standard pushed settings screen

[marionbarker]

Almost approved by code review and test.

The screens navigation headers seem more consistent now.

• If a feature screen has a tab is in the toolbar, you use the toolbar to get to another screen.
• If the feature screen can only be reached via the Menu, you use a blue X at upper right to return to Menu
• The Settings screen uses an X at upper left to return to Menu
  • The sub-screens in Settings use a < at upper left to return to Settings
  • The exception is the Tab sub-screen

Please modify the Tab sub-screen to use the < at upper left to return to Settings.
Right now it uses a Done on upper right.

[marionbarker]

Some Features (that are not selected as tabs) say "< Menu" and others say "<" and of course Statistics is a little different because it has "< Menu" and "Refresh".

When Statistics is a tab, it does not have anything on navigation row - so can't hit refresh. (Do we need the refresh button?)

• When Alarms is not a tab, it has "<"
• When Remove is not a tab, it has "< Menu"

[marionbarker]

Approved by Test.

This reorganization works as expected. IMO a big improvement.

LGTM