feat(parsers.concat): Added new parser to concat chunks and split messages at custom headers

[olo667]

Summary

New parser plugin which allows for stitching chunks of data and splitting them into messages based on configurable message headers. Useful for parsing small chunks of data which are part of a larger structure. After synthesizing the messages, passes them onto a secondary embedded parser to convert them to metrics.

Enables embedding of parsers into one another by using an 'embedded_parser' field in the config, and a parser implementing the ParserPlugin interface.

Checklist

• No AI generated code was used in this PR
• AI generated code used in this PR follows the InfluxData Policy on AI-Generated Code Contributions

Related issues

resolves #19259

[telegraf-tiger]

Thanks so much for the pull request!
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[telegraf-tiger]

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. 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