buildsystem: Move to meson for building the project

Meson will allow us to:
- Verify the used rust compiler is recent enough
- Install ressources such as a .desktop files, icons, etc.

meson.build

@@ -0,0 +1,30 @@
+project(
+  'helvum',
+  'rust',
+  version: '0.3.0',
+  license: 'GPL-3.0',
+  meson_version: '>=0.50.0'
+)
+
+dependency('glib-2.0', version: '>= 2.48')
+dependency('gtk4',     version: '>= 4.0.0')
+dependency('libpipewire-0.3')
+
+rust_version = meson.get_compiler('rust').version()
+min_rust_version = '1.54.0'
+if rust_version < min_rust_version
+  error('Rust version too old: Required version is ' + min_rust_version + ' but actual version is ' + rust_version)
+endif
+
+cargo = find_program('cargo', required: true)
+cargo_script = find_program('build-aux/cargo.sh')
+
+prefix = get_option('prefix')
+bindir = prefix / get_option('bindir')
+
+cargo_sources = files(
+  'Cargo.toml',
+  'Cargo.lock',
+)
+
+subdir('src')