Merge bitcoin/bitcoin#25065: [kernel 2c/n] Introduce kernel::Context, encapsulate global init/teardown

d87784ac87 kernel: SanityChecks: Return an error struct (Carl Dong)
265d6393bf Move init::SanityCheck to kernel::SanityCheck (Carl Dong)
fed085a1a4 init: Initialize globals with kernel::Context's life (Carl Dong)
7d03feef81 kernel: Introduce empty and unused kernel::Context (Carl Dong)
eeb4fc20c5 test: Use Set/UnsetGlobals in BasicTestingSetup (Carl Dong)

Pull request description:

  The full `init/common.cpp` is dependent on things like ArgsManager (which we wish to remove from libbitcoinkernel in the future) and sanity checks. These aren't necessary for libbitcoinkernel so we only extract the portion that is necessary (namely `init::{Set,Unset}Globals()`.

ACKs for top commit:
  theuni:
    ACK d87784ac87
  vasild:
    ACK d87784ac87

Tree-SHA512: cd6b4923ea1865001b5f0caed9a4ff99c198d22bf74154d935dc09a47fda22ebe585ec912398cea69f722454ed1dbb4898faab5a2d02fb4c5e719c5c8d71a3f9

src/test/util/setup_common.cpp

@@ -12,6 +12,7 @@
 #include <consensus/validation.h>
 #include <crypto/sha256.h>
 #include <init.h>
+#include <init/common.h>
 #include <interfaces/chain.h>
 #include <net.h>
 #include <net_processing.h>
@@ -126,8 +127,7 @@ BasicTestingSetup::BasicTestingSetup(const std::string& chainName, const std::ve
     InitLogging(*m_node.args);
     AppInitParameterInteraction(*m_node.args);
     LogInstance().StartLogging();
-    SHA256AutoDetect();
-    ECC_Start();
+    m_node.kernel = std::make_unique<kernel::Context>();
     SetupEnvironment();
     SetupNetworking();
     InitSignatureCache();
@@ -147,7 +147,6 @@ BasicTestingSetup::~BasicTestingSetup()
     LogInstance().DisconnectTestLogger();
     fs::remove_all(m_path_root);
     gArgs.ClearArgs();
-    ECC_Stop();
 }
 
 ChainTestingSetup::ChainTestingSetup(const std::string& chainName, const std::vector<const char*>& extra_args)