Track platform-specific Rust build sources

Author: wysaid

bindings/rust/build.rs

@@ -420,6 +420,58 @@ Please vendor the sources into bindings/rust/native/, or set CCAP_SOURCE_DIR to
             "cargo:rerun-if-changed={}/src/ccap_convert_c.cpp",
             ccap_root.display()
         );
+
+        // Platform-specific sources
+        #[cfg(target_os = "macos")]
+        {
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_imp_apple.mm",
+                ccap_root.display()
+            );
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_convert_apple.cpp",
+                ccap_root.display()
+            );
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_file_reader_apple.mm",
+                ccap_root.display()
+            );
+        }
+
+        #[cfg(target_os = "linux")]
+        {
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_imp_linux.cpp",
+                ccap_root.display()
+            );
+        }
+
+        #[cfg(target_os = "windows")]
+        {
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_imp_windows.cpp",
+                ccap_root.display()
+            );
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_file_reader_windows.cpp",
+                ccap_root.display()
+            );
+        }
+
+        // SIMD-specific sources
+        #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
+        {
+            println!(
+                "cargo:rerun-if-changed={}/src/ccap_convert_avx2.cpp",
+                ccap_root.display()
+            );
+        }
+
+        // Always built in build-from-source mode to provide hasNEON() symbol.
+        println!(
+            "cargo:rerun-if-changed={}/src/ccap_convert_neon.cpp",
+            ccap_root.display()
+        );
     }
 
     // Generate bindings