This effectively reverts a3cb309e7c from PR #30194.
That PR reduced the multi_index type signatures as recommended upstream, but
this is no longer supported as of boost 1.91 because it is no longer necessary.
1.91 drops support for the pre-c++11 work-arounds that bloated the type
signatures to begin with.
The upstream `BOOST_MULTI_INDEX_ENABLE_MPL_SUPPORT` define is meant to provide
compatibility with removed features, but it does not work for this case. Using
`indexed_by` directly when defining the `multi_index` (as opposed to inheriting
from it) works with all versions, and avoids the use of the back-compat define.
This is a slight regression when building against boost < 1.91 because the
bloated type signatures are reintroduced in that case, but it's not significant
enough to go to the trouble of introducing version detection and ifdefs.
Github-Pull: #35175
Rebased-From: 0bc9d354dfd8074d1c36a891a69b6585a8775c65
The src/node/ directory contains code that needs to access node state
(state in CChain, CBlockIndex, CCoinsView, CTxMemPool, and similar
classes).
Code in src/node/ is meant to be segregated from code in
src/wallet/ and src/qt/, to ensure wallet and GUI
code changes don't interfere with node operation, to allow wallet and GUI code
to run in separate processes, and to perhaps eventually allow wallet and GUI
code to be maintained in separate source repositories.
As a rule of thumb, code in one of the src/node/,
src/wallet/, or src/qt/ directories should avoid
calling code in the other directories directly, and only invoke it indirectly
through the more limited src/interfaces/ classes.
This directory is at the moment
sparsely populated. Eventually more substantial files like
src/validation.cpp and
src/txmempool.cpp might be moved there.
546598b736