Rebrand hush3 to DragonX and share RandomX dataset across mining threads

Minimal rebrand (see compliant-rebrand branch for full rebrand):
- Rename binaries: hushd/hush-cli/hush-tx → dragonxd/dragonx-cli/dragonx-tx
- Default to DRAGONX chain params without -ac_* flags (randomx, blocktime=36, private=1)
- Update configure.ac: AC_INIT([DragonX],[1.0.0])
- Update client version string and user-agent to /DragonX:1.0.0/
- Add chainparams.cpp with DRAGONX network parameters
- Update build.sh, miner.cpp, pow.cpp for DragonX
- Add bootstrap-dragonx.sh utility script
- Update .gitignore for release directory

Share single RandomX dataset across all mining threads:
- Add RandomXDatasetManager with readers-writer lock, reducing RAM from
  ~2GB per thread to ~2GB total plus ~2MB per thread for the VM scratchpad
- Add LogProcessMemory() diagnostic helper for Linux and Windows

src/Makefile.am

@@ -94,11 +94,11 @@ noinst_PROGRAMS =
 TESTS =
 
 #if BUILD_BITCOIND
-  bin_PROGRAMS += hushd
+  bin_PROGRAMS += dragonxd
 #endif
 
 if BUILD_BITCOIN_UTILS
-  bin_PROGRAMS += hush-cli hush-tx
+  bin_PROGRAMS += dragonx-cli dragonx-tx
 endif
 if ENABLE_WALLET
   bin_PROGRAMS += wallet-utility
@@ -453,16 +453,16 @@ nodist_libbitcoin_util_a_SOURCES = $(srcdir)/obj/build.h
 #
 
 # hushd binary #
-hushd_SOURCES = bitcoind.cpp
-hushd_CPPFLAGS = -fPIC $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
-hushd_CXXFLAGS = -fPIC $(AM_CXXFLAGS) $(PIE_FLAGS)
-hushd_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
+dragonxd_SOURCES = bitcoind.cpp
+dragonxd_CPPFLAGS = -fPIC $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
+dragonxd_CXXFLAGS = -fPIC $(AM_CXXFLAGS) $(PIE_FLAGS)
+dragonxd_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 if TARGET_WINDOWS
-hushd_SOURCES += bitcoind-res.rc
+dragonxd_SOURCES += bitcoind-res.rc
 endif
 
-hushd_LDADD = \
+dragonxd_LDADD = \
   $(LIBBITCOIN_SERVER) \
   $(LIBBITCOIN_COMMON) \
   $(LIBUNIVALUE) \
@@ -476,10 +476,10 @@ hushd_LDADD = \
   $(LIBRANDOMX)
 
 if ENABLE_WALLET
-hushd_LDADD += $(LIBBITCOIN_WALLET)
+dragonxd_LDADD += $(LIBBITCOIN_WALLET)
 endif
 
-hushd_LDADD += \
+dragonxd_LDADD += \
   $(BOOST_LIBS) \
   $(BDB_LIBS) \
   $(SSL_LIBS) \
@@ -490,27 +490,27 @@ hushd_LDADD += \
   $(LIBZCASH_LIBS)
 
 if TARGET_DARWIN
-hushd_LDADD += libcc.dylib $(LIBSECP256K1)
+dragonxd_LDADD += libcc.dylib $(LIBSECP256K1)
 endif
 if TARGET_WINDOWS
-hushd_LDADD += libcc.dll $(LIBSECP256K1)
+dragonxd_LDADD += libcc.dll $(LIBSECP256K1)
 endif
 if TARGET_LINUX
-hushd_LDADD += libcc.so $(LIBSECP256K1)
+dragonxd_LDADD += libcc.so $(LIBSECP256K1)
 endif
 
 # [+] Decker: use static linking for libstdc++.6.dylib, libgomp.1.dylib, libgcc_s.1.dylib
 if TARGET_DARWIN
-hushd_LDFLAGS += -static-libgcc
+dragonxd_LDFLAGS += -static-libgcc
 endif
 
 # hush-cli binary #
-hush_cli_SOURCES = bitcoin-cli.cpp
-hush_cli_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(EVENT_CFLAGS)
-hush_cli_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
-hush_cli_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
+dragonx_cli_SOURCES = bitcoin-cli.cpp
+dragonx_cli_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(EVENT_CFLAGS)
+dragonx_cli_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
+dragonx_cli_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 if TARGET_DARWIN
-hush_cli_LDFLAGS += -static-libgcc
+dragonx_cli_LDFLAGS += -static-libgcc
 endif
 
 # wallet-utility binary #
@@ -522,10 +522,10 @@ wallet_utility_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 endif
 
 if TARGET_WINDOWS
-hush_cli_SOURCES += bitcoin-cli-res.rc
+dragonx_cli_SOURCES += bitcoin-cli-res.rc
 endif
 
-hush_cli_LDADD = \
+dragonx_cli_LDADD = \
 	$(LIBBITCOIN_CLI) \
 	$(LIBUNIVALUE) \
 	$(LIBBITCOIN_UTIL) \
@@ -554,16 +554,16 @@ wallet_utility_LDADD = \
 endif
 
 # hush-tx binary #
-hush_tx_SOURCES = hush-tx.cpp
-hush_tx_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
-hush_tx_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
-hush_tx_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
+dragonx_tx_SOURCES = hush-tx.cpp
+dragonx_tx_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
+dragonx_tx_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
+dragonx_tx_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 if TARGET_WINDOWS
-hush_tx_SOURCES += bitcoin-tx-res.rc
+dragonx_tx_SOURCES += bitcoin-tx-res.rc
 endif
 
-hush_tx_LDADD = \
+dragonx_tx_LDADD = \
   $(LIBUNIVALUE) \
   $(LIBBITCOIN_COMMON) \
   $(LIBBITCOIN_UTIL) \
@@ -574,7 +574,7 @@ hush_tx_LDADD = \
   $(LIBZCASH_LIBS) \
   $(LIBRANDOMX)
 
-hush_tx_LDADD += $(BOOST_LIBS) $(CRYPTO_LIBS)
+dragonx_tx_LDADD += $(BOOST_LIBS) $(CRYPTO_LIBS)
 
 # Zcash Protocol Primitives
 libzcash_a_SOURCES = \