Merge bitcoin/bitcoin#27615: msvc: Rename libbitcoinconsensus to libbitcoin_consensus and other adjustments

a94d75fa81 msvc: Do not define `HAVE_CONSENSUS_LIB` (Hennadii Stepanov)
cf6ff1031b msvc: Clean up `libbitcoin_consensus` source files (Hennadii Stepanov)
30aee016f1 scripted-diff: Rename `libbitcoinconsensus` to `libbitcoin_consensus` (Hennadii Stepanov)

Pull request description:

  The current Autotools-based build system operates with two build artifacts:
  - [`LIBBITCOIN_CONSENSUS`](3777c75d14/src/Makefile.am (L31)) which is [defined as](https://github.com/bitcoin/bitcoin/blob/master/doc/design/libraries.md) "Stable, backwards-compatible consensus functionality used by _libbitcoin_node_ and _libbitcoin_wallet_"
  - [`LIBBITCOINCONSENSUS`](3777c75d14/src/Makefile.am (L42)) which is [defined as](https://github.com/bitcoin/bitcoin/blob/master/doc/design/libraries.md) "Shared library build of static _libbitcoin_consensus_ library"

  The way how the `libbitcoinconsensus.vcxproj` project is used in the MSVC build system obviously shows that it is the former use case.

  This PR makes the related adjustments to the MSVC build system.

ACKs for top commit:
  sipsorcery:
    ACK a94d75fa81.

Tree-SHA512: 1144e13ee2b428ce14be8f76729744830c502a07814eb03e2aa6b8e009d8936fd13743e3f36ef3f31fac0e3979eb9af23e6a1364f151df49b3ae18dbd14cbf99

build_msvc/test_bitcoin-qt/test_bitcoin-qt.vcxproj

@@ -28,7 +28,7 @@
     <ClCompile Include="$(GeneratedFilesOutDir)\moc\moc_wallettests.cpp" />
   </ItemGroup>
   <ItemGroup>
-    <ProjectReference Include="..\libbitcoinconsensus\libbitcoinconsensus.vcxproj">
+    <ProjectReference Include="..\libbitcoin_consensus\libbitcoin_consensus.vcxproj">
       <Project>{2b384fa8-9ee1-4544-93cb-0d733c25e8ce}</Project>
     </ProjectReference>
     <ProjectReference Include="..\libbitcoin_cli\libbitcoin_cli.vcxproj">