feat(logging): Implement structured logging

[srebhan]

Summary

Structured logging is a machine-readable way of outputting logs and useful when automatically processing the produced logs.
This PR implements a structured log-target producing JSON formatted structured logs. It is output to a logfile, if specified, or to stderr otherwise similar to the usual text logger. Additionally, the PR deprecates the file and stderr targets and replaces them with a text target as that's what the output is. The decision to use a file or stderr is the done based on the logfile setting

Checklist

• No AI generated code was used in this PR

Related issues

resolves #8815

[powersj]

This looks great. My only question is around the config option values.

[srebhan]

We should introduce a new logformat option and completely the logtarget one completely instead of reusing it.

[telegraf-tiger]

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Downloads for additional architectures and packages are available below.

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Artifact URLs

DEB	RPM	TAR GZ	ZIP
amd64.deb	aarch64.rpm	darwin_amd64.tar.gz	windows_amd64.zip
arm64.deb	armel.rpm	darwin_arm64.tar.gz	windows_arm64.zip
armel.deb	armv6hl.rpm	freebsd_amd64.tar.gz	windows_i386.zip
armhf.deb	i386.rpm	freebsd_armv7.tar.gz
i386.deb	ppc64le.rpm	freebsd_i386.tar.gz
mips.deb	riscv64.rpm	linux_amd64.tar.gz
mipsel.deb	s390x.rpm	linux_arm64.tar.gz
ppc64el.deb	x86_64.rpm	linux_armel.tar.gz
riscv64.deb		linux_armhf.tar.gz
s390x.deb		linux_i386.tar.gz
		linux_mips.tar.gz
		linux_mipsel.tar.gz
		linux_ppc64le.tar.gz
		linux_riscv64.tar.gz
		linux_s390x.tar.gz