Merge #18244: rpc: fundrawtransaction and walletcreatefundedpsbt also lock manually selected coins

6d1f51343c [rpc] fundrawtransaction, walletcreatefundedpsbt lock manually selected coins (Sjors Provoost)

Pull request description:

  When using `fundrawtransaction` and `walletcreatefundedpsbt` with `lockUnspents`, it would only lock automatically selected coins, not manually selected coins. That doesn't make much sense to me if the goal is to prevent accidentally double-spending yourself before you broadcast a transaction.

  Note that when  creating a transaction, manually selected coins are automatic "unlocked" (or more accurately: the lock is ignored). Earlier versions of this PR introduced an error when a locked coin is manually selected, but this idea was abandoned after some discussion. An application that uses this RPC should either rely on automatic coin selection (with `lockUnspents`) or handle lock concurrency itself with manual coin selection. In particular it needs to make sure to avoid/pause calls with automatic coin selection between calling `lockunspent` and the subsequent spending RPC.

  See #7518 for historical background.

ACKs for top commit:
  meshcollider:
    Code review ACK 6d1f51343c
  fjahr:
    Code review ACK 6d1f51343c

Tree-SHA512: 8773c788d92f2656952e1beac147ba9956b8c5132d474e0880e4c89ff53642928b4cbfcd1cb3d17798b9284f02618a8830c93a9f7a4733e5bded96adff1d5d4d

doc/release-notes-18244.md

@@ -0,0 +1,7 @@
+Updated RPCs
+------------
+
+- `fundrawtransaction` and `walletcreatefundedpsbt` when used with the `lockUnspents`
+   argument now lock manually selected coins, in addition to automatically selected
+   coins. Note that locked coins are never used in automatic coin selection, but
+   can still be manually selected.