fix(rust): Resolve critical build and API issues

- Fix CMakeLists.txt circular dependency (remove ccap <- ccap-rust dep)
- Add Windows Media Foundation libraries for video playback support
- Fix error type in set_new_frame_callback (use InvalidParameter)
- Document global error callback memory management behavior

Fixes:
- Windows build failures in CI
- Circular dependency preventing CMake configuration
- Incorrect error type returned from callback registration

Author: wysaid

CMakeLists.txt

@@ -400,10 +400,8 @@ if (CCAP_BUILD_RUST)
                 COMMENT "Testing Rust bindings"
                 DEPENDS ccap-rust
         )
-        # Add to main build if requested
-        if (CCAP_IS_ROOT_PROJECT)
-            add_dependencies(ccap ccap-rust)
-        endif ()
+        # Rust bindings are optional, do not add to main build automatically
+        # Users can explicitly build with: cmake --build . --target ccap-rust
         message(STATUS "ccap: Rust bindings targets added:")
         message(STATUS "  ccap-rust: Build Rust bindings")
         message(STATUS "  ccap-rust-test: Test Rust bindings")

bindings/rust/build.rs

@@ -165,6 +165,10 @@ fn main() {
         println!("cargo:rustc-link-lib=strmiids");
         println!("cargo:rustc-link-lib=ole32");
         println!("cargo:rustc-link-lib=oleaut32");
+        // Media Foundation libraries for video file playback
+        println!("cargo:rustc-link-lib=mfplat");
+        println!("cargo:rustc-link-lib=mfreadwrite");
+        println!("cargo:rustc-link-lib=mfuuid");
     }
 
     // Tell cargo to invalidate the built crate whenever the wrapper changes

bindings/rust/src/provider.rs

@@ -328,6 +328,15 @@ impl Provider {
     }
 
     /// Set error callback for camera errors
+    /// 
+    /// # Memory Safety
+    /// 
+    /// This is a **global** callback that persists for the lifetime of the program.
+    /// The callback memory is intentionally leaked as it's meant to be set once
+    /// and used throughout the application lifetime.
+    /// 
+    /// If you need to change or remove the callback, consider using instance-level
+    /// callbacks via `set_new_frame_callback` instead.
     pub fn set_error_callback<F>(callback: F)
     where
         F: Fn(i32, &str) + Send + Sync + 'static,
@@ -444,7 +453,7 @@ impl Provider {
             unsafe {
                 let _ = Box::from_raw(callback_ptr);
             }
-            Err(CcapError::CaptureStartFailed)
+            Err(CcapError::InvalidParameter("Failed to set frame callback".to_string()))
         }
     }