refactor(downloader): turn DownloadManager into downloader registry

Reshape DownloadManager from a hard-coded VCS match into a registry of
DownloaderInterface instances keyed by source type, mirroring
Composer's DownloadManager — with prefer-source/dist preferences, an
IO handle, and a files cache. ArchiveManager now resolves dist
sources through a shared DownloadManager instead of calling
download_dist directly, and Composer::require / try_load take an IO
so it flows through the factory wiring.

1 files changed, 8 insertions, 0 deletions

diff --git a/crates/mozart-core/src/util/filesystem.rs b/crates/mozart-core/src/util/filesystem.rs
new file mode 100644
index 0000000..efcb0fb
--- /dev/null
+++ b/crates/mozart-core/src/util/filesystem.rs
@@ -0,0 +1,8 @@
+#[derive(Default)]
+pub struct Filesystem;
+
+impl Filesystem {
+    pub fn new() -> Self {
+        Self {}
+    }
+}