Use :logger_handler formatter for JSON

[ruslandoga]

This PR switches from Logger backends to :logger handlers.

Card: https://3.basecamp.com/5308029/buckets/29267832/card_tables/cards/7610404292

Plan:

• remove :console backend
• WIP add "native" JSON formatter
• Sentry.LoggerBackend -> Sentry.LoggerHandler
• ensure overload protection

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Should JSON formatter be a library?

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Other people might find it useful. I didn't find anything like it at the time of my original implementation (it was all about formatters for backends or backends back then). But maybe there is something out there now. I'll need to check.

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UPDATE: Probably not, since a very popular LoggerJSON supports handlers as of 7 months ago.

Would it make sense to switch to it? Right now its "Basic" format is a bit different from what ex_json_logger was using. But seems like it might allow configuration.

Logger.info("hello")
Logger.info("hello", request_id: 1)

LoggerJSON:

{"message":"hello","time":"2024-11-26T08:45:10.982Z","metadata":{},"severity":"info"}
{"message":"hello","time":"2024-11-26T08:45:10.982Z","metadata":{"request_id":1},"severity":"info"}

ExJsonLogger @ 1.4.0 (currently used):

{"time":"2024-11-26 15:48:43.186","msg":"hello","level":"info"}
{"time":"2024-11-26 16:03:19.836","msg":"hello","level":"info","request_id":1}

This PR:

{"level":"info","time":"2024-11-26 15:47:13.136","msg":"hello"}
{"level":"info","time":"2024-11-27 11:54:52.559","msg":"hello","request_id":1}

Differences between LoggerJSON and ExJsonLogger:

• UTC vs system time (can be configured with utc_log Logger option in ExJsonLogger and this PR)
• different key names
• meta is nested instead of merged
• rescues exceptions during formatting (not sure if necessary)

Differences between this PR and LoggerJSON:

• more similar to the default Logger.Formatter (same configuration, same logic in most cases)
• is a bit faster since it performs less work / doesn't require configurability

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Tests

• Automated tests have been added
• This PR does not require tests

Changelog

• This PR does not make a user-facing change

Documentation

• This change does not need a documentation update

Dark mode

• This PR does not change the UI

[ruslandoga]

Closing in favor of #4862 to keep changes minimal.