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.
+ HelpExampleRpc("loadwallet", "\"test.dat\"")
        );
    std::string wallet_file = request.params[0].get_str();
    std::string error;
    fs::path wallet_path = fs::absolute(wallet_file, GetWalletDir());
    if (fs::symlink_status(wallet_path).type() == fs::file_not_found) {
        throw JSONRPCError(RPC_WALLET_NOT_FOUND, "Wallet " + wallet_file + " not found.");
    } else if (fs::is_directory(wallet_path)) {
        
        fs::path wallet_dat_file = wallet_path / "wallet.dat";
        if (fs::symlink_status(wallet_dat_file).type() == fs::file_not_found) {
            throw JSONRPCError(RPC_WALLET_NOT_FOUND, "Directory " + wallet_file + " does not contain a wallet.dat file.");
        }
    }
    std::string warning;
    if (!CWallet::Verify(wallet_file, false, error, warning)) {
        throw JSONRPCError(RPC_WALLET_ERROR, "Wallet file verification failed: " + error);
    }
    std::shared_ptr<CWallet> const wallet = CWallet::CreateWalletFromFile(wallet_file, fs::absolute(wallet_file, GetWalletDir()));
    if (!wallet) {
        throw JSONRPCError(RPC_WALLET_ERROR, "Wallet loading failed.");
    }
    AddWallet(wallet);
    wallet->postInitProcess();
    UniValue obj(UniValue::VOBJ);
    obj.pushKV("name", wallet->GetName());
    obj.pushKV("warning", warning);
    return obj;
}
static UniValue createwallet(const JSONRPCRequest& request)