Merge bitcoin/bitcoin#28186: kernel: Prune leveldb headers

d8f1222ac5 refactor: Correct dbwrapper key naming (TheCharlatan)
be8f159ac5 build: Remove leveldb from BITCOIN_INCLUDES (TheCharlatan)
c95b37d641 refactor: Move CDBWrapper leveldb members to their own context struct (TheCharlatan)
c534a615e9 refactor: Split dbwrapper CDBWrapper::EstimateSize implementation (TheCharlatan)
586448888b refactor: Move HandleError to dbwrapper implementation (TheCharlatan)
dede0eef7a refactor: Split dbwrapper CDBWrapper::Exists implementation (TheCharlatan)
a5c2eb5748 refactor: Fix logging.h includes (TheCharlatan)
84058e0eed refactor: Split dbwrapper CDBWrapper::Read implementation (TheCharlatan)
e4af2408f2 refactor: Pimpl leveldb::Iterator for CDBIterator (TheCharlatan)
ef941ff128 refactor: Split dbwrapper CDBIterator::GetValue implementation (TheCharlatan)
b7a1ab5cb4 refactor: Split dbwrapper CDBIterator::GetKey implementation (TheCharlatan)
d7437908cd refactor: Split dbwrapper CDBIterator::Seek implementation (TheCharlatan)
ea8135de7e refactor: Pimpl leveldb::batch for CDBBatch (TheCharlatan)
b9870c920d refactor: Split dbwrapper CDBatch::Erase implementation (TheCharlatan)
532ee812a4 refactor: Split dbwrapper CDBBatch::Write implementation (TheCharlatan)
afc534df9a refactor: Wrap DestroyDB in dbwrapper helper (TheCharlatan)

Pull request description:

  Leveldb headers are currently included in the `dbwrapper.h` file and thus available to many of Bitcoin Core's source files. However, leveldb-specific functionality should be abstracted by the `dbwrapper` and does not need to be available to the rest of the code. Having leveldb included in a widely-used header such as `dbwrapper.h` bloats the entire project's header tree.

  The `dbwrapper` is a key component of the libbitcoinkernel library. Future users of this library would not want to contend with  having the leveldb headers exposed and potentially polluting their project's namespace.

  For these reasons, the leveldb headers are removed from the `dbwrapper` by moving leveldb-specific code to the implementation file and creating a [pimpl](https://en.cppreference.com/w/cpp/language/pimpl) where leveldb member variables are indispensable. As a final step, the leveldb include flags are removed from the `BITCOIN_INCLUDES` and moved to places where the dbwrapper is compiled.

  ---

  This pull request is part of the [libbitcoinkernel project](https://github.com/bitcoin/bitcoin/issues/27587), and more specifically its stage 1 step 3 "Decouple most non-consensus headers from libbitcoinkernel".

ACKs for top commit:
  stickies-v:
    re-ACK d8f1222ac5
  MarcoFalke:
    ACK d8f1222ac5  🔠

Tree-SHA512: 0f58309be165af0162e648233451cd80fda88726fc10c0da7bfe4ec2ffa9afe63fbf7ffae9493698d3f39653b4ad870c372eee652ecc90ab1c29d86c387070f3

src/init.cpp

@@ -33,6 +33,7 @@
 #include <interfaces/chain.h>
 #include <interfaces/init.h>
 #include <interfaces/node.h>
+#include <logging.h>
 #include <mapport.h>
 #include <net.h>
 #include <net_permissions.h>