[Auto Pin Confirm]: Changes to allow PIN auto confirm feature to be controllable by the user

- Add SwitchPreference to allow user to control the pin auto confirm feature
- Add Checkbox option during the PIN setup in Security app
- Disable the opt-in checkbox during SUW entry point for PIN setup
- Update SwitchPreference availability appropriately according to current PIN length
- Update the pin_auto_confirm setting appropriately according to state of switchPreference or checkbox state (in PIN setup)
- Update the error-message when PIN Too short to let user know six digit is recommended

Bug: 262926000
Bug: 262936383
Bug: 262934702
Bug: 262935305
Test: Manual Test
Test: atest SettingsRoboTests
Change-Id: Ib9e09bd5ce44652158e77f80e8be19c4dd50f3bf