Collect unbound histogram stats

[zeloff]

Summary

The histogram data on unbound response times is more informative than the (already exported) mean and median values.

Checklist

• [x ] No AI generated code was used in this PR

Related issues

resolves #16451

The bounds of the histogram's buckets are hardcoded (see util/timehist.c on the unbound source) so it is safe to assume they will remain constant. Therefore, it is sufficient to only export the lower bound of each bucket, in the field name.

[telegraf-tiger]

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

Download PR build artifacts for linux_amd64.tar.gz, darwin_arm64.tar.gz, and windows_amd64.zip.
Downloads for additional architectures and packages are available below.

⚠️ This pull request increases the Telegraf binary size by 1.01 % for linux amd64 (new size: 283.4 MB, nightly size 280.6 MB)

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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