Add multisig batch group overflow fault logging. #1484

Job	Run time
msvc (windows-latest, StaticDebug, x64, vs2022, *)	58s
msvc (windows-2025-vs2026, StaticRelease, x64, vs2026, *)	58s
gnu (ubuntu-24.04, debug, static, gcc-13, g++-13, --coverage -fprofile-update=atomic, lcov, --bui...	58s
presets (ubuntu-24.04, nix-gnu-release-shared, clang-18, clang++-18, --build-boost, --build-secp2...	58s
cmake (ubuntu-24.04, release, static, clang-19, clang++-19, clang-19 clang++-19, --build-boost, -...	58s
gnu (ubuntu-24.04, release, dynamic, clang-18, clang++-18, --build-boost, --build-secp256k1, --en...	58s
presets (ubuntu-24.04, nix-gnu-debug-static, gcc-12, g++-12, --build-boost, --build-secp256k1)	58s
cmake (ubuntu-24.04, debug, dynamic, gcc-16, g++-16, g++-16 gcc-16, --build-boost, --build-secp25...	58s
gnu (macos-latest, release, static, clang, clang++, --build-boost, --build-secp256k1, --enable-is...	58s
gnu (ubuntu-24.04, release, static, gcc-15, g++-15, g++-15 gcc-15, --build-boost, --build-secp256...	58s
cmake (ubuntu-24.04, release, dynamic, gcc-12, g++-12, --build-boost, --build-secp256k1)	58s
gnu (ubuntu-24.04, debug, dynamic, clang-19, clang++-19, clang-19 clang++-19, --build-boost, --bu...	58s
cmake (ubuntu-24.04, debug, static, gcc-14, g++-14, --build-boost, --build-secp256k1)	58s
cmake (macos-latest, debug, dynamic, clang, clang++, --build-boost, --build-secp256k1)	58s
	13m 32s

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