fix: resolve Rust FFI compilation errors and simplify build

- Fix duplicate Clone implementation conflict in CodexConfig
- Add Default derive to CodexConfigRust for unwrap_or_default()
- Fix temporary lifetime issues in find_codex_binary()
- Remove unused imports (CString, CodexEvent)
- Update Makefile rust-build-release to target arm64 only (no x86_64/lipo)
- Add gitignore rules for Rust build artifacts

.gitignore

@@ -46,3 +46,9 @@ app.*.map.json
 /android/app/debug
 /android/app/profile
 /android/app/release
+
+# Rust / FFI artifacts
+/rust/target/
+/rust/Cargo.lock
+/macos/Frameworks/*.dylib
+/macos/Frameworks/*.a

Makefile

@@ -51,16 +51,9 @@ clean: ## Remove generated artifacts
 
 rust-build: rust-build-release ## Build Rust FFI library (release mode)
 
-rust-build-release: ## Build Rust FFI library in release mode
+rust-build-release: ## Build Rust FFI library for macOS (arm64)
 	cd rust && cargo build --release --target aarch64-apple-darwin
-	cd rust && cargo build --release --target x86_64-apple-darwin
-	@echo "Creating universal binary..."
-	mkdir -p rust/target/universal
-	lipo -create \
-		rust/target/aarch64-apple-darwin/release/libcodex_ffi.dylib \
-		rust/target/x86_64-apple-darwin/release/libcodex_ffi.dylib \
-		-output rust/target/universal/libcodex_ffi.dylib || true
-	@echo "Universal binary created at rust/target/universal/"
+	@echo "Rust FFI library built successfully"
 
 rust-build-debug: ## Build Rust FFI library in debug mode
 	cd rust && cargo build --target aarch64-apple-darwin

rust/src/lib.rs

@@ -11,7 +11,7 @@ pub use error::CodexError;
 pub use runtime::{CodexRuntime, CodexConfig, CodexConfigRust, ThreadHandle, RuntimeState};
 pub use types::{CodexResult, CodexMessage, CodexEvent};
 
-use std::ffi::{CStr, CString};
+use std::ffi::CStr;
 use std::os::raw::c_char;
 
 /// FFI-exported initialization function.
@@ -55,14 +55,13 @@ pub unsafe extern "C" fn codex_runtime_destroy(runtime: *mut CodexRuntime) {
 /// Must be called with valid pointers.
 #[no_mangle]
 pub unsafe extern "C" fn codex_start_thread(
-    runtime: *mut CodexRuntime,
+    _runtime: *mut CodexRuntime,
     cwd: *const c_char,
 ) -> ThreadHandle {
-    if runtime.is_null() || cwd.is_null() {
+    if cwd.is_null() {
         return ThreadHandle::null();
     }
     
-    let _runtime = &mut *runtime;
     let _cwd = CStr::from_ptr(cwd);
     
     ThreadHandle::new(0)
@@ -75,7 +74,7 @@ pub unsafe extern "C" fn codex_start_thread(
 #[no_mangle]
 pub unsafe extern "C" fn codex_send_message(
     runtime: *mut CodexRuntime,
-    thread: ThreadHandle,
+    _thread: ThreadHandle,
     message: *const c_char,
 ) -> i32 {
     if runtime.is_null() || message.is_null() {

rust/src/runtime.rs

@@ -5,7 +5,6 @@ use std::os::raw::c_char;
 use std::path::PathBuf;
 
 use crate::error::CodexError;
-use crate::types::CodexEvent;
 
 /// Configuration for Codex runtime.
 #[derive(Debug, Clone)]
@@ -100,24 +99,8 @@ impl CodexConfig {
     }
 }
 
-impl Clone for CodexConfig {
-    fn clone(&self) -> Self {
-        // Safe to clone the pointers as they're just pointers to strings
-        CodexConfig {
-            codex_path: self.codex_path,
-            working_directory: self.working_directory,
-            sandbox_mode: self.sandbox_mode,
-            approval_policy: self.approval_policy,
-            model: self.model,
-            api_key: self.api_key,
-            gateway_url: self.gateway_url,
-            debug: self.debug,
-        }
-    }
-}
-
 /// Rust-native config type.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Default)]
 pub struct CodexConfigRust {
     pub codex_path: Option<String>,
     pub working_directory: Option<String>,
@@ -218,11 +201,13 @@ impl CodexRuntime {
 
         // Check common locations
         let home = std::env::var("HOME").unwrap_or_default();
-        let paths = vec![
+        let cargo_path = format!("{}/.cargo/bin/codex", home);
+        let local_path = format!("{}/.local/bin/codex", home);
+        let paths = [
             "/usr/local/bin/codex",
             "/opt/homebrew/bin/codex",
-            &format!("{}/.cargo/bin/codex", home),
-            &format!("{}/.local/bin/codex", home),
+            cargo_path.as_str(),
+            local_path.as_str(),
         ];
 
         for path in paths {