rec: handle applicable dynamic parts of YAML only config when reloading Lua config

[omoerbeek]

Short description

Fixes #16673

This is all a bit tricky and in need of a more thorough refactoring. The existing regression tests exercise some of the reloading (see test_Protobuf.py). I modified the SimpleForward regression test to also use reloading, so more cases are covered. Setting this as ready for review. The refactoring can be done a a separate PR, maybe for next release.

Checklist

I have:

• read the CONTRIBUTING.md document
• read and accepted the Developer Certificate of Origin document, including the AI Policy, and added a "Signed-off-by" to my commits
• compiled this code
• tested this code
• included documentation (including possible behaviour changes)
• documented the code
• added or modified regression test(s)
• added or modified unit test(s)

[coveralls]

Pull Request Test Coverage Report for Build 21252389698

Details

• 40 of 42 (95.24%) changed or added relevant lines in 1 file are covered.
• 12803 unchanged lines in 145 files lost coverage.
• Overall coverage increased (+0.04%) to 71.518%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pdns/recursordist/rec_channel_rec.cc	40	42	95.24%

Files with Coverage Reduction	New Missed Lines	%
pdns/base64.cc	1	92.75%
pdns/protozero-trace.hh	1	68.56%
pdns/recursordist/rec_channel_rec.cc	1	35.3%
pdns/burtle.hh	2	98.19%
pdns/dns.cc	2	88.29%
pdns/dnsdistdist/dnsdist-lua-bindings-kvs.cc	2	48.0%
pdns/dnsdistdist/dnsdist-lua.hh	2	34.25%
pdns/dnsdistdist/dnsdist-opentelemetry.cc	2	94.93%
pdns/epollmplexer.cc	2	85.71%
pdns/json.hh	2	0.0%

Totals
Change from base Build 21246135242:	0.04%
Covered Lines:	128826
Relevant Lines:	165243

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💛 - Coveralls