Dev: DB transactions after v4.3

[kenjis]

We need to discuss:

• [x] Allow manual DB transactions even when DBDebug is true.
  • #6917
• DBDebug will be deprecated in the future if possible.
  • Perhaps this setting should not be eliminated.
  • This setting is widely used and needs a long period of time before removing it.
• [ ] Add resetTransStatus() method ?
  • #8767
• [ ] Model validation error and transaction. See https://forum.codeigniter.com/showthread.php?tid=84887&pid=403200#pid403200

See https://github.com/codeigniter4/CodeIgniter4/pull/6886#issuecomment-1325774111, https://github.com/codeigniter4/CodeIgniter4/pull/6886#issuecomment-1324182519