better hypr-data prod guard

Author: yujonglee

crates/data/build.rs

@@ -1,5 +1,11 @@
 fn main() {
-    if std::env::var("PROFILE").as_deref() == Ok("release") {
+    let is_release = std::env::var("PROFILE").as_deref() == Ok("release");
+    // CARGO_PRIMARY_PACKAGE is only set for the crate being directly compiled,
+    // not for its (dev-)dependencies. A non-primary crate compiled in release
+    // mode is a dev-dependency of `cargo test --release`, which is fine.
+    let is_primary = std::env::var("CARGO_PRIMARY_PACKAGE").is_ok();
+
+    if is_release && is_primary {
         panic!(
             "\n\nhypr-data is a test-only crate.\nDo not add it to [dependencies]; use [dev-dependencies] instead.\n"
         );