Change rfd features to enable manual builds on Linux.

rfd wasn't building on Linux, since its default features appear to be
for Windows. This commit changes them to work on Linux. TODO test on
Windows.

Cargo.toml

@@ -30,7 +30,7 @@ nalgebra = "0.33.0"
 once_cell = "1.19.0"
 rand = "0.8.5"
 reqwest = { version = "0.12.7", features = ["blocking", "json"] }
-rfd = "0.15.0"
+rfd = { version = "0.15.1", default-features = false, features = ["tokio"] }
 semver = "1.0.23"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"