Adds helper build script to build ffi libs locally and copy to plugins folder (#197)

* My new build script to build macos and android locally and copy ffi lib artifacts into plugins

* Added section in README for the new build helper script

Author: MaxHeimbrock

BuildScripts~/build_ffi_locally.sh

@@ -0,0 +1,86 @@
+#!/bin/bash
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+MANIFEST="$ROOT/client-sdk-rust~/Cargo.toml"
+BASE_DST="$ROOT/Runtime/Plugins"
+BASE_TARGET="$ROOT/client-sdk-rust~/target"
+
+RED='\033[0;31m'
+YELLOW='\033[0;33m'
+GREEN='\033[0;32m'
+RESET='\033[0m'
+
+usage() {
+    echo "Usage: $0 <platform>"
+    echo ""
+    echo "Platforms:"
+    echo "  macos       Build for aarch64-apple-darwin"
+    echo "  android     Build for aarch64-linux-android"
+    exit 1
+}
+
+if [ $# -ne 1 ]; then
+    echo -e "${RED}Error: Expected exactly one argument.${RESET}"
+    usage
+fi
+
+PLATFORM="$1"
+
+case "$PLATFORM" in
+    macos)
+        echo "Building for macOS (aarch64-apple-darwin)..."
+        cargo build \
+            --manifest-path "$MANIFEST" \
+            --release \
+            --workspace \
+            -p livekit \
+            --target aarch64-apple-darwin
+        BUILD_STATUS=$?
+
+        SRC="$BASE_TARGET/aarch64-apple-darwin/release/liblivekit_ffi.dylib"
+        DST="$BASE_DST/ffi-macos-arm64/liblivekit_ffi.dylib"
+        ;;
+    android)
+        echo "Building for Android (aarch64-linux-android)..."
+        pushd "$ROOT/client-sdk-rust~" > /dev/null
+        cargo ndk \
+            --target aarch64-linux-android \
+            build \
+            --release \
+            -p livekit \
+            --workspace \
+            -v \
+            --no-default-features \
+            --features "rustls-tls-webpki-roots"
+        BUILD_STATUS=$?
+        popd > /dev/null
+
+        SRC="$BASE_TARGET/aarch64-linux-android/release/liblivekit_ffi.so"
+        DST="$BASE_DST/ffi-android-arm64/liblivekit_ffi.so"
+        ;;
+    *)
+        echo -e "${RED}Error: Unknown platform '$PLATFORM'.${RESET}"
+        usage
+        ;;
+esac
+
+if [ $BUILD_STATUS -ne 0 ]; then
+    echo -e "${RED}Build failed. Aborting copy.${RESET}"
+    exit 1
+fi
+
+echo ""
+echo "Copying to $DST..."
+cp -f "$SRC" "$DST"
+
+if [ $? -eq 0 ]; then
+    echo -e "${GREEN}Copied $(basename "$DST") successfully.${RESET}"
+    if [ "$PLATFORM" = "macos" ]; then
+        echo ""
+        echo -e "${YELLOW}WARNING: QUIT UNITY TO LOAD NEW LIB${RESET}"
+    fi
+else
+    echo -e "${RED}Failed to copy $(basename "$DST"). Check that the source file exists and the destination directory is writable.${RESET}"
+    exit 1
+fi

README.md

@@ -48,7 +48,15 @@ You can use the package manager to import local `client-sdk-unity` into your Uni
 
 Or you can import the git url `https://github.com/livekit/client-sdk-unity.git` from the package manager.
 
+### Building Livekit plugins locally
 
+For local development, initialize the git submodule containing the Rust code for the LiveKit plugin libraries. 
+
+There is a [helper script](https://github.com/livekit/client-sdk-unity/blob/main/BuildScripts~/build_ffi_locally.sh) to build the libraries locally and exchange the downloaded libraries with the build artifacts.
+
+Currently, the build script supports the following arguments:
+- macos
+- android
 
 ### iOS