Give prevalence to process level over primary/module levels

[v0idpwn]

The docs incorrectly implied that Logger.put_process_level/2 allowed one to decrease the logger level for a process. This is not possible with this function.

[v0idpwn]

Reproducing the issue:

Erlang/OTP 27 [erts-15.0] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [jit:ns]

Interactive Elixir (1.17.1) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> require Logger
Logger
iex(2)> Logger.configure(level: :info)
:ok
iex(3)> Logger.put_process_level(self(), :debug)
:ok
iex(4)> Logger.debug("hello?")
:ok
iex(5)> Logger.info("info")

09:46:25.063 [info] info
:ok
iex(6)> Logger.put_process_level(self(), :error)
:ok
iex(7)> Logger.info("info again")
:ok
iex(8)> Logger.error("error")

09:46:47.350 [error] error
:ok
iex(9)>

[josevalim]

It seems the put_module_level makes a bypass, so if that's the case, maybe we should try to mirror it here?

[v0idpwn]

Pushed the change to prefer process level over global level. Will write a test.

[josevalim]

We still need to check if this level is allowed by either calling :logger_config.allow(level) or by calling :logger_config.allow(level, module) if we want still want to look up the module.

[v0idpwn]

Calling :logger_config.allow(level, module) there would give precedence for module/primary level. Pushed some fixes and I believe we have the expected behaviour now :)

[v0idpwn]

I'm not sure what's the behaviour that was being tested here. This started failing when I made capture_log not change log level

[v0idpwn]

There's a big problem with this approach: elixir and erlang logs behave under different rules. I think this is not desirable and probably we can't merge.

[v0idpwn]

Closing per the above. Will fix documentation in a separate PR.