Test Details Overview

Remove the large votes flag and batch hashes at the confirm_req and vote limits (#5245)

* Remove the large votes rollout flag

The disable_large_votes flag lowered the mutable nano::network
statics confirm_req_hashes_max and confirm_ack_hashes_max from 255
to 7 and 12. With it set, the vote replier refused any confirm_req
of more than 12 pairs, so a peer's request of 13 to 255 pairs went
unanswered. The statics go, and the command line option stays so
that existing launch commands still parse: `--help` lists it as
deprecated and it has no effect.

The limits now live on the types that own the wire format:
confirm_req::max_hashes for the (hash, root) pairs a request
carries, and the existing vote::max_hashes for the hashes of a vote,
and so of a confirm_ack. Both message constructors assert against
them in place of the bare 256. The confirmation solicitor and the
vote replier bound requests by confirm_req::max_hashes, and the
vote generator bounds its broadcast batches by vote::max_hashes.

* Batch hashes into confirm_reqs and votes at their limits

confirm_req::batch_hashes and vote::batch_hashes split a list into
the requests or votes it fits, in order, next to the max_hashes
each one applies.

The confirmation solicitor sends one confirm_req per batch.
voting_policy::sign splits its permits over as many votes as they
need and every representative signs each of them, so a vote never
outgrows vote::max_hashes, whatever a caller passes. The vote
replier no longer depends on a full request fitting one vote.

The vote tests move out of vote_processor.cpp into their own
vote.cpp, next to the new batching tests.

* Fix the final-vote check in packed_timestamp and test the vote type

packed_timestamp asserted that the maximum timestamp only packs
with the final duration, but compared the unmasked argument against
timestamp_max, so a timestamp with any low bit set, such as the
all-ones marker with a lower duration, packed into a non-final vote
at the maximum timestamp. It now compares the masked timestamp.
Both of its checks are release asserts, since a vote signed past
them carries a timestamp the whole network ranks above every
genuine one, and each says what went wrong and with which exponent.

hashes_string had no callers, operator!= is synthesized from
operator== since C++20, and operator== compares every member, so it
is defaulted. The declared copy constructor only suppressed the
implicit move.

The vote suite covered the batching and little else: of vote.cpp it
ran 12 of 22 functions and 11 of 24 branches, and empty_hashes
asserted nothing. It now covers the wire format round trip,
truncated and over-long streams, what the signed hash does and does
not cover, validate against each kind of tampering, equality, the
final vote marker, every duration exponent and the JSON form, and
death tests pin both packed_timestamp checks. empty_hashes checks
that the empty vote validates, serializes to the fixed part alone
and reads back equal.

The vote_uniquer tests move out of conflicts.cpp, where they had
nothing to do with conflicts, next to the type they test, with
plain hashes in place of the blocks they built only to hash.

* Add is_debug_build beside the platform predicates

Code and tests can ask whether debug_assert is compiled in through
a consteval predicate, like the sanitizer and platform ones in
config.hpp, instead of testing NDEBUG where it matters. Nothing
uses it yet.

* Move vote from nano/lib to nano/secure

A vote is a signed statement about blocks, consensus state like the
ledger and the voting policy rather than a plain utility, so it
lives in secure with them. nano_messages already links secure, and
nothing in nano_lib used the type.

The store's db_val converted a database value into a vote for a
vote table that no longer exists; the conversion had no callers and
goes, which keeps the store below secure. The messages forward
header takes its declarations from secure/fwd.hpp, which chains to
lib/fwd.hpp.

* Document the vote class in the one-line header style

Give every function and member of nano::vote a short purpose comment
and add a class overview covering what the signature spans, how the
timestamp packs the duration exponent and where the hash count lives.
Spell out the error conventions of deserialize () and validate () and
tell the two digests apart. Drop the cpp comment blocks the header now
covers and the TODO on size ().

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Type: commit

Hash: f1af0ffb182478b5b821b9f44fb5599a81ca3ac2

Created: today

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gr0v1ty/nano-node:f1af0ffb182478b5b821b9f44fb5599a81ca3ac2