[iOS] Make logs shorter

[JonnyBurger]

Summary

Currently all logs include current time, including timezone and nanoseconds, as well as the thread ID and the log level.

While it is detailed, I find that it is also very noisy. I rarely need those things.

• Most of the time timing is irrelevant, so I removed it completely. Developers can also add the current time to the logs themselves easily. I would at least remove nanaoseconds and timezone.

• Thread ID is often irrelevant (Prior to this PR I did not even know what [tid:123] meant). The only interesting case is when the Thread ID is com.facebook.react.JavaScript. Then I add [JS] in front of it.

• Log level I have also removed because as a developer I have very little control over it.

Changelog

[iOS] [Changed] - Log format

Test Plan

Tested it manually.

[pull-bot]

Messages

📖

📋 Verify Changelog Format - A changelog entry has the following format: [CATEGORY] [TYPE] - Message. CATEGORY may be: General iOS Android JavaScript Internal (for changes that do not need to be called out in the release notes) TYPE may be: Added, for new features. Changed, for changes in existing functionality. Deprecated, for soon-to-be removed features. Removed, for now removed features. Fixed, for any bug fixes. Security, in case of vulnerabilities. MESSAGE may answer "what and why" on a feature level. Use this to briefly tell React Native users about notable changes.

Generated by 🚫 dangerJS against d2b06c9

[cpojer]

@JonnyBurger could you add a screenshot to compare the before/after?

[JonnyBurger]

0.59.9 Log:

With this PR applied:

With this PR applied and #25382 applied:

With this PR, #25382, #25381 applied:

The last one missing would be to kill these nw_socket messages!

[akshetpandey]

At least to me, this makes it harder to read the logs since the indent levels at which the important parts of the log start are now significantly different

[cpojer]

I discussed this with others and it seems that people are preferring to keep the date/time stamp as is because it aligns with other logging on iOS. Since the logs already point out that it's a JS log, I let's keep it as is.

Note that the next version of RN + CLI will log console.log calls to the terminal where Metro is running.