The `generate` RPC method:
- was introduced in 2010
- is now only used for testing
- reaches across multiple components (wallet, mining)

I propose we remove the wallet `generate` RPC method and update all tests to use the `generatetoaddress` RPC method. We can do this non-invasively in the test framework by adding a `generate` method to `TestNode` so that the individual tests do not need to be updated. We could also add a `generate` alias to the `generatetoaddress` RPC method.

Doing this removes a wallet->server dependency and simplifies the wallet->server interface (#10973).

I'm opening this issue before implementing in case anyone has objections.
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    if (request.fHelp || request.params.size() < 2 || request.params.size() > 5)
        throw std::runtime_error(
                            "walletcreatefundedpsbt [{\"txid\":\"id\",\"vout\":n},...] [{\"address\":amount},{\"data\":\"hex\"},...] ( locktime ) ( replaceable ) ( options bip32derivs )\n"
                            "\nCreates and funds a transaction in the Partially Signed Transaction format. Inputs will be added if supplied inputs are not enough\n"
                            "Implements the Creator and Updater roles.\n"
                            "\nArguments:\n"
                            "1. \"inputs\"                (array, required) A json array of json objects\n"
                            "     [\n"
                            "       {\n"
                            "         \"txid\":\"id\",      (string, required) The transaction id\n"
                            "         \"vout\":n,         (numeric, required) The output number\n"
                            "         \"sequence\":n      (numeric, optional) The sequence number\n"
                            "       } \n"
                            "       ,...\n"
                            "     ]\n"
                            "2. \"outputs\"               (array, required) a json array with outputs (key-value pairs)\n"
                            "   [\n"
                            "    {\n"
                            "      \"address\": x.xxx,    (obj, optional) A key-value pair. The key (string) is the bitcoin address, the value (float or string) is the amount in " + CURRENCY_UNIT + "\n"
                            "    },\n"
                            "    {\n"
                            "      \"data\": \"hex\"        (obj, optional) A key-value pair. The key must be \"data\", the value is hex-encoded data\n"
                            "    }\n"