Auto merge of #17722 - joshka:jm/logs, r=Veykril

feat: use vscode log format for client logs

This change updates the log format to use the vscode log format instead
of the custom log format, by replacing the `OutputChannel` with a
`LogOutputChannel` and using the `debug`, `info`, `warn`, and `error`
methods on it. This has the following benefits:

- Each log level now has its own color and the timestamp is in a more
  standard format
- Inspect output (e.g. the log of the config object) is now colored
- Error stack traces are now shown in the output
- The log level is now controlled on the output tab by clicking the gear
  icon and selecting "Debug" or by passing the `--log` parameter to
  vscode. The `trace.extension` setting has been marked as deprecated.

Motivation:
The large uncolored unformatted log output with a large config object logged whenever it changes has always dominated the logs. This subjectively has made it that looking to see what the client is doing has always been a bit disappointing. That said, there's only 17 log messages total in the client. Hopefully by making the logs more visually useful this will encourage adding more appropriate debug level messages in future.

Incidentally, it might be worth only logging the config change message at a debug level instead of an info level to reduce the noise.

Author: bors