Merge bitcoin/bitcoin#28246: wallet: Use CTxDestination in CRecipient instead of just scriptPubKey

ad0c469d98 wallet: Use CTxDestination in CRecipient rather than scriptPubKey (Andrew Chow)
07d3bdf4eb Add PubKeyDestination for P2PK scripts (Andrew Chow)
1a98a51c66 Allow CNoDestination to represent a raw script (Andrew Chow)
8dd067088d Make WitnessUnknown members private (Andrew Chow)

Pull request description:

  For silent payments, we want to provide a `SilentPaymentsDestination` to be used as the recipient, which requires `CRecipient` to use something other than just the `scriptPubKey` as we cannot know the output script for a silent payment prior to transaction creation. `CTxDestination` seems like the obvious place to add a `SilentPaymentsDestination` as it is our internal representation of an address.

  In order to still allow paying to arbitrary scriptPubKeys (e.g. for data carrier outputs, or the user hand crafted a raw transaction that they have given to `fundrawtransaction`), `CNoDestination` is changed to contain raw scripts.

  Additionally, P2PK scripts are now interpreted as a new `PubKeyDestination` rather than `PKHash`. This results in some things that would have given an address for P2PK scripts to no longer do so. This is arguably more correct.

  `ExtractDestination`'s behavior is slightly changed for the above. It now returns `true` for those destinations that have addresses, so P2PK scripts now result in `false`. Even though it returns false for `CNoDestination`, the script will now be included in that `CNoDestination`.

  Builds on #28244

ACKs for top commit:
  josibake:
    ACK https://github.com/bitcoin/bitcoin/pull/28246/commits/ad0c469d98c51931b98b7fd937c6ac3eeaed024e

Tree-SHA512: ef3f8f3c7284779d9806c77c85b21caf910a79a1f7e7f1b51abcc0d7e074f14e00abf30f625a13075e41d94dad6202c10ddff462c0ee74c2ca4aab585b145a52

src/wallet/test/spend_tests.cpp

@@ -27,7 +27,7 @@ BOOST_FIXTURE_TEST_CASE(SubtractFee, TestChain100Setup)
     // leftover input amount which would have been change to the recipient
     // instead of the miner.
     auto check_tx = [&wallet](CAmount leftover_input_amount) {
-        CRecipient recipient{GetScriptForRawPubKey({}), 50 * COIN - leftover_input_amount, /*subtract_fee=*/true};
+        CRecipient recipient{PubKeyDestination({}), 50 * COIN - leftover_input_amount, /*subtract_fee=*/true};
         constexpr int RANDOM_CHANGE_POSITION = -1;
         CCoinControl coin_control;
         coin_control.m_feerate.emplace(10000);

src/wallet/test/wallet_tests.cpp

@@ -645,7 +645,7 @@ void TestCoinsResult(ListCoinsTest& context, OutputType out_type, CAmount amount
 {
     LOCK(context.wallet->cs_wallet);
     util::Result<CTxDestination> dest = Assert(context.wallet->GetNewDestination(out_type, ""));
-    CWalletTx& wtx = context.AddTx(CRecipient{{GetScriptForDestination(*dest)}, amount, /*fSubtractFeeFromAmount=*/true});
+    CWalletTx& wtx = context.AddTx(CRecipient{*dest, amount, /*fSubtractFeeFromAmount=*/true});
     CoinFilterParams filter;
     filter.skip_locked = false;
     CoinsResult available_coins = AvailableCoins(*context.wallet, nullptr, std::nullopt, filter);