Add fuzz inputs

[maflcko]

C.f. last one: #234

mv fuzz_corpora fuzz_inputs_moved
../b-c/bld-cmake/test/fuzz/test_runner.py -l DEBUG --par $( nproc ) --m_dir ./fuzz_inputs_moved/  --m_dir ./results_from_working_farm --m_dir ../etc/... ./fuzz_corpora
git restore -- ./fuzz_corpora
git add ./fuzz_corpora
git commit -m "Add fuzz inputs"

[maflcko]

main: https://drahtbot.space/host_reports/DrahtBot/reports/coverage_fuzz/monotree/bd4f4782f23b59f8/c87ae4dd4daf320f/fuzz.coverage/index.html
this pull: https://drahtbot.space/host_reports/DrahtBot/reports/coverage_fuzz/monotree/bd4f4782f23b59f8/6be1610ae3cd6507/fuzz.coverage/index.html

[maflcko]

Only 25 new lines of code covered. My fuzzing server was down for a good chunk of time, so maybe this is expected.

Also, Murch submitted recently in December: #246

Not sure what to do. Seems fine to merge, or to close, and they'll be submitted again later.

[maflcko]

This includes a few regression tests for psbt stuff, so maybe it can be merged just to include those?

[murchandamus]

Only 25 new lines of code covered. My fuzzing server was down for a good chunk of time, so maybe this is expected.

Also, Murch submitted recently in December: #246

Not sure what to do. Seems fine to merge, or to close, and they'll be submitted again later.

It seems like we might be getting close to full coverage on many of the established fuzz targets. What would be the downsides of merging? Are you worried about the additional time to run the full harness while there is little coverage improvement? If that were the worry, should we perhaps prune more often instead of not merging?

[maflcko]

It seems like we might be getting close to full coverage on many of the established fuzz targets.

The Bitcoin Core code changes, so over time the coverage will degrade and only catch up with fresh inputs. But maybe you are right and the Bitcoin core changes didn't invalidate prior coverage, so there was not a lot new to discover.

What would be the downsides of merging?

No downside, just eating a bit of space and CI time.

I think I'll go ahead and merge this now.