Add NEST Desktop

This is not how this should be done in the end… we should use mktemp to generate unique and fresh temp files. For now this restores functionality to build from r/o folders.

packages/nest-desktop/package.py

+# Copyright 2013-2024 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack.package import *
+
+
+class NestDesktop(PythonPackage):
+    """NEST Desktop is a web-based GUI for NEST Simulator and other 
+    simulators of spiking networks."""
+
+    homepage = "http://www.nest-desktop.github.io"
+    pypi     = "nest-desktop/nest_desktop-4.0.5.tar.gz"
+    git      = "https://github.com/nest-desktop/nest-desktop.git"
+
+    maintainers = ['spreizer']
+
+    version('4.0.5', sha256='fffd472bf2f5e1a4398ad82cbe626e1b306d68b0e3a31ffcca71cd3449d8ef2f')
+
+    variant("nest", default=False)
+
+    depends_on("python@3.9:", type=("build", "run"))
+    depends_on("py-setuptools", type=("build"))
+
+    depends_on('nest@3.0:', type=('run'), when='+nest')
+