Stratum v2 Template Provider common functionality

[Sjors]

Moved from bitcoin#30475.

Based on:

• Noise encryption Sv2 noise #66
• Messages and transport layer Stratum v2 Transport #67
• Sv2Connman Stratum v2 connman #50

And the following interface changes:

• Introduce waitTipChanged() mining interface, replace RPCNotifyBlockChange, drop CRPCSignals & g_best_block bitcoin/bitcoin#30409
• Mining interface: getCoinbaseMerklePath() and submitSolution() bitcoin/bitcoin#30955
• Have createNewBlock() wait for tip, make rpc handle shutdown during long poll and wait methods bitcoin/bitcoin#31785 (not needed, this PR has a workaround)
• Add waitNext() to BlockTemplate interface bitcoin/bitcoin#31283
  • Make m_tip_block std::optional bitcoin/bitcoin#31325
• refactor: mining interface 30955 followups bitcoin/bitcoin#31197
• Drop script_pub_key arg from createNewBlock bitcoin/bitcoin#31318
• Prune mining interface bitcoin/bitcoin#31196
• Add destroy to BlockTemplate schema bitcoin/bitcoin#31288
• Set notifications m_tip_block in LoadChainTip() bitcoin/bitcoin#31346
• Have createNewBlock() return a BlockTemplate interface bitcoin/bitcoin#30440

As well as:

• miner: timelock the coinbase to the mined block's height bitcoin/bitcoin#32155
  • opt-out with -coinbaselocktime=0

This contains all Template Provider functionality that can be used by both #68 and the IPC based sidecar alternative #48.

[Sjors]

Updated to the latest interface changes proposed in bitcoin#30409 and #53.

[Sjors]

Rebased for CMake

[Sjors]

One test still seems brittle:

src/test/sv2_template_provider_tests.cpp(256): fatal error: in "sv2_template_provider_tests/client_tests": critical check tester.GetBlockTemplateCount() == 3 has failed [2 != 3]

[Sjors]

Moved TemplateProvider from node to common so that in #48 bitcoin-mine does not depend on bitcoin-node.

[Sjors]

Occasional failing on CentOS probably means the tests need to be made more robust. https://cirrus-ci.com/task/5262823086882816

[Sjors]

Rebased after bitcoin#31785 landed, which completes the interface changes needed for the Template Provider. Dropped the use of waitTipChanged() on startup and added a shutdown check in ThreadSv2ClientHandler().

[Sjors]

CI fails because since bitcoin#29307 we have to fclose files. I'll update 9e6d5d6 to do that.

[Sjors]

Note to self for the next update, apply:

diff --git a/src/sv2/template_provider.cpp b/src/sv2/template_provider.cpp
index a4331c6cb3..d83b86be69 100644
--- a/src/sv2/template_provider.cpp
+++ b/src/sv2/template_provider.cpp
@@ -66,7 +66,7 @@ Sv2TemplateProvider::Sv2TemplateProvider(interfaces::Mining& mining) : m_mining{
     version_pubkey_bytes[1] = 0;
     m_authority_pubkey = XOnlyPubKey(authority_key.GetPubKey());
     std::copy(m_authority_pubkey.begin(), m_authority_pubkey.end(), version_pubkey_bytes.begin() + 2);
-    LogInfo("Template Provider authority key: %s\n", EncodeBase58Check(version_pubkey_bytes));
+    LogPrintLevel(BCLog::SV2, BCLog::Level::Info, "Template Provider authority key: %s\n", EncodeBase58Check(version_pubkey_bytes));
     LogTrace(BCLog::SV2, "Authority key: %s\n", HexStr(m_authority_pubkey));