feat(components): add ThermoState generators and Eurovent backend demo

crates/fluids/build.rs

@@ -0,0 +1,18 @@
+//! Build script for entropyk-fluids crate.
+//! 
+//! This build script can optionally compile CoolProp C++ library when the
+//! "coolprop" feature is enabled.
+
+use std::env;
+
+fn main() {
+    let coolprop_enabled = env::var("CARGO_FEATURE_COOLPROP").is_ok();
+    
+    if coolprop_enabled {
+        println!("cargo:rustc-link-lib=dylib=coolprop");
+        println!("cargo:rerun-if-changed=build.rs");
+    }
+    
+    // Tell Cargo to rerun this script if any source files change
+    println!("cargo:rerun-if-changed=build.rs");
+}