Merge bitcoin/bitcoin#31375: multiprocess: Add bitcoin wrapper executable

a5ac43d98d doc: Add release notes describing bitcoin wrapper executable (Ryan Ofsky)
258bda80c0 doc: Mention bitcoin wrapper executable in documentation (Ryan Ofsky)
d2739d75c9 build: add bitcoin.exe to windows installer (Sjors Provoost)
ba649c0006 ci: Run multiprocess tests through wrapper executable (Ryan Ofsky)
29bdd743bb test: Support BITCOIN_CMD environment variable (Ryan Ofsky)
9c8c68891b multiprocess: Add bitcoin wrapper executable (Ryan Ofsky)
5076d20fdb util: Add cross-platform ExecVp and GetExePath functions (Ryan Ofsky)

Pull request description:

  Intended to make bitcoin command line features more discoverable and allow installing new multiprocess binaries in libexec/ instead of bin/ so they don't cause confusion.

  Idea and implementation of this were discussed in https://github.com/bitcoin/bitcoin/issues/30983.

  ---

  Initial implementation of this feature is deliberately minimal so the UX can evolve in response to feedback and there are not too many details to debate and discuss in a single PR. But many improvements are possible or planned:

  - Adding manpage and bash completions.
  - Showing nicer error messages that detect if an executable isn't installed and suggest how to fix [(comment)](https://github.com/bitcoin/bitcoin/pull/31375#discussion_r2073194474)
  - Showing wrapper command lines in subcommand in help output [(comment)](https://github.com/bitcoin/bitcoin/pull/31375#discussion_r2077800405). This could be done conditionally as suggested in the comment or be unconditional.
  - Showing wrapper command lines in subcommand error output. There is a bitcoin-cli error pointed out in [(comment)](https://github.com/bitcoin/bitcoin/pull/31375#discussion_r2091152243) that is needlessly confusing.
  - Integrating help so `bitcoin help subcommand` invokes `bitcoin subcommand -h`. `bitcoin -h subcommand` should also be supported and be equivalent [(comment)](https://github.com/bitcoin/bitcoin/pull/31375#discussion_r2093116725)
  - Adding support for `bitcoin-util` subcommands. Ideal interface would probably be more like `bitcoin grind` not `bitcoin util grind` but this has been punted for now. Supporting subcommands directly would require some ArgsManager modifications
  - Adding a dedicated python functional test for the wrapper. Right now there is some CI coverage by setting the `BITCOIN_CMD` variable, but this doesn't cover things like the help output and version output, and support for different directory layouts.
  - Better `--multiprocess` (`-m`) / `--monolithic` (`-M`) default selection. Right now, default is monolithic but it probably makes sense to chose more intelligently depending on whether -ipc options are enabled and what binaries are available.
  - Maybe parsing `bitcoin.conf` and supporting options to control wrapper behavior like custom locations or preferences or aliases.
  - Better command command line usability. Allow combining short options like (`-ah`). Allow fuzzy matching of subcommands or suggestions if you misspell. (suggested by stickies in review club)
  - Not directly related to this PR but `bitcoin-cli named` implementation used by the wrapper should do a better job disambiguating named arguments from base64 arguments ending in = as pointed out in [(comment)](https://github.com/bitcoin/bitcoin/pull/31375#discussion_r2091886628)

  ---

  This PR is part of the [process separation project](https://github.com/bitcoin/bitcoin/issues/28722). A review club meeting for it took place in https://bitcoincore.reviews/31375

ACKs for top commit:
  Sjors:
    utACK a5ac43d98d
  achow101:
    ACK a5ac43d98d
  vasild:
    ACK a5ac43d98d
  theStack:
    ACK a5ac43d98d
  ismaelsadeeq:
    fwiw my last review implied an ACK a5ac43d98d
  hodlinator:
    ACK a5ac43d98d

Tree-SHA512: 570e6a4ff8bd79ef6554da3d01f36c0a7c6d2dd7dace8f8732eca98f4a8bc2284474a9beadeba783114fe2f3dd08b2041b3da7753bae0b7f881ec50668cb821f

cmake/module/GenerateSetupNsi.cmake

@@ -7,6 +7,7 @@ function(generate_setup_nsi)
   set(abs_top_builddir ${PROJECT_BINARY_DIR})
   set(CLIENT_URL ${PROJECT_HOMEPAGE_URL})
   set(CLIENT_TARNAME "bitcoin")
+  set(BITCOIN_WRAPPER_NAME "bitcoin")
   set(BITCOIN_GUI_NAME "bitcoin-qt")
   set(BITCOIN_DAEMON_NAME "bitcoind")
   set(BITCOIN_CLI_NAME "bitcoin-cli")

cmake/module/Maintenance.cmake

@@ -23,7 +23,7 @@ function(add_maintenance_targets)
     return()
   endif()
 
-  foreach(target IN ITEMS bitcoind bitcoin-qt bitcoin-cli bitcoin-tx bitcoin-util bitcoin-wallet test_bitcoin bench_bitcoin)
+  foreach(target IN ITEMS bitcoin bitcoind bitcoin-qt bitcoin-cli bitcoin-tx bitcoin-util bitcoin-wallet test_bitcoin bench_bitcoin)
     if(TARGET ${target})
       list(APPEND executables $<TARGET_FILE:${target}>)
     endif()
@@ -43,7 +43,7 @@ function(add_maintenance_targets)
 endfunction()
 
 function(add_windows_deploy_target)
-  if(MINGW AND TARGET bitcoin-qt AND TARGET bitcoind AND TARGET bitcoin-cli AND TARGET bitcoin-tx AND TARGET bitcoin-wallet AND TARGET bitcoin-util AND TARGET test_bitcoin)
+  if(MINGW AND TARGET bitcoin AND TARGET bitcoin-qt AND TARGET bitcoind AND TARGET bitcoin-cli AND TARGET bitcoin-tx AND TARGET bitcoin-wallet AND TARGET bitcoin-util AND TARGET test_bitcoin)
     find_program(MAKENSIS_EXECUTABLE makensis)
     if(NOT MAKENSIS_EXECUTABLE)
       add_custom_target(deploy
@@ -59,6 +59,7 @@ function(add_windows_deploy_target)
     add_custom_command(
       OUTPUT ${PROJECT_BINARY_DIR}/bitcoin-win64-setup.exe
       COMMAND ${CMAKE_COMMAND} -E make_directory ${PROJECT_BINARY_DIR}/release
+      COMMAND ${CMAKE_STRIP} $<TARGET_FILE:bitcoin> -o ${PROJECT_BINARY_DIR}/release/$<TARGET_FILE_NAME:bitcoin>
       COMMAND ${CMAKE_STRIP} $<TARGET_FILE:bitcoin-qt> -o ${PROJECT_BINARY_DIR}/release/$<TARGET_FILE_NAME:bitcoin-qt>
       COMMAND ${CMAKE_STRIP} $<TARGET_FILE:bitcoind> -o ${PROJECT_BINARY_DIR}/release/$<TARGET_FILE_NAME:bitcoind>
       COMMAND ${CMAKE_STRIP} $<TARGET_FILE:bitcoin-cli> -o ${PROJECT_BINARY_DIR}/release/$<TARGET_FILE_NAME:bitcoin-cli>