scm: new guile/scheme bindings

This implements the new scm/guile bindings for mu, to replace the deprecated
guile/ (at some point in the future).

For now, we allow for creating a guile shell with mu support.

scm/mu-scm-contact.cc

@@ -0,0 +1,36 @@
+/*
+** Copyright (C) 2025 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
+**
+** This program is free software; you can redistribute it and/or modify it
+** under the terms of the GNU General Public License as published by the
+** Free Software Foundation; either version 3, or (at your option) any
+** later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software Foundation,
+** Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+**
+*/
+
+
+#include "mu-scm-contact.hh"
+
+using namespace Mu::Scm;
+
+SCM
+Mu::Scm::to_scm(const Contact& contact)
+{
+	static SCM email{scm_from_utf8_symbol("email")};
+	static SCM name{scm_from_utf8_symbol("name")};
+
+	SCM alist = scm_acons(email, to_scm(contact.email), SCM_EOL);
+	if (!contact.name.empty())
+		alist = scm_acons(name, to_scm(contact.name), alist);
+
+	return alist;
+}