Merge bitcoin/bitcoin#22219: multiprocess: Start using init makeNode, makeChain, etc methods

e4709c7b56 Start using init makeNode, makeChain, etc methods (Russell Yanofsky)

Pull request description:

  Use `interfaces::Init::make*` methods instead of `interfaces::Make*` functions, so interfaces can be constructed differently in different executable without having to change any code. (So for example `bitcoin-gui` can make an `interfaces::Node` pointer that communicates with a `bitcoin-node` subprocess, while `bitcoin-qt` can make an `interfaces::Node` pointer that controls node code in the same process.)

  ---

  This PR is part of the [process separation project](https://github.com/bitcoin/bitcoin/projects/10). The commit was first part of larger PR #10102.

ACKs for top commit:
  jamesob:
    reACK e4709c7b56
  achow101:
    ACK e4709c7b56
  benthecarman:
    utACK e4709c7b56

Tree-SHA512: 580c1979dbb2ef444157c8e53041e70d15ddeee77e5cbdb34f70b6d228cc2d2fe3843825f172da84e506200c58f7e0932f7cd4c006bb5058c1f4e43259394834

src/init.cpp

@@ -26,6 +26,7 @@
 #include <index/txindex.h>
 #include <init/common.h>
 #include <interfaces/chain.h>
+#include <interfaces/init.h>
 #include <interfaces/node.h>
 #include <mapport.h>
 #include <miner.h>
@@ -1063,7 +1064,7 @@ bool AppInitLockDataDirectory()
 
 bool AppInitInterfaces(NodeContext& node)
 {
-    node.chain = interfaces::MakeChain(node);
+    node.chain = node.init->makeChain();
     // Create client interfaces for wallets that are supposed to be loaded
     // according to -wallet and -disablewallet options. This only constructs
     // the interfaces, it doesn't load wallet data. Wallets actually get loaded