feat: add workspace-level root package

Add a root package `mingling-workspace` with an empty `main.rs` to
improve Cargo workspace compatibility.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..f328e4d
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1 @@
+fn main() {}