Merge origin/master into dev: restore the mingw -Wa,-mbig-obj flag

dev branched from the release line before 1c3523aac and so lost -Wa,-mbig-obj
from util/build-win.sh. Without it the Windows cross-compile fails at link: large
template/boost-heavy translation units exceed the PE/COFF ~32k-section limit, and
GNU ld emits "dangerous relocation" on .pdata and crashes. v1.1.0 therefore could
not produce a win64 binary at all.

The merge brings only that one file back. util/build-win.sh is the only file both
sides touched, and the two edits are ~20 lines apart, so it auto-merges keeping
both fixes: -Wa,-mbig-obj on the configure line and -DARCH=default on the cmake
line. Verified after merging that dev's own work is intact -- the extended
checkpoint table, the guarded RandomX dedup, the 1.1.0 version bump, and
ARCH=default in the other two build scripts.

No C++ changed; the only delta from the pre-merge dev is the shell script.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

util/build-win.sh

@@ -16,7 +16,10 @@ cd ..
 
 ./autogen.sh
 
-CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site CXXFLAGS="-DPTW32_STATIC_LIB -DCURL_STATICLIB -fopenmp -pthread" ./configure --prefix="${PREFIX}" --host=x86_64-w64-mingw32 --enable-static --disable-shared
+# -Wa,-mbig-obj: the daemon's large template/boost-heavy TUs (e.g. asyncrpcoperation.cpp) exceed the
+# standard PE/COFF ~32k-section limit, which makes GNU ld emit "dangerous relocation" on .pdata and
+# crash. The bigobj COFF variant lifts that limit (same flag Bitcoin Core sets for the mingw host).
+CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site CXXFLAGS="-DPTW32_STATIC_LIB -DCURL_STATICLIB -fopenmp -pthread -Wa,-mbig-obj" ./configure --prefix="${PREFIX}" --host=x86_64-w64-mingw32 --enable-static --disable-shared
 
 # Build CryptoConditions stuff
 WD=$PWD