feat: add --helix-version flag to install script

Allow users to override the installed version instead of always using latest

install.sh

@@ -35,6 +35,7 @@ OLDER_GPU=false
 HF_TOKEN=""
 PROXY=https://get.helix.ml
 EXTRA_OLLAMA_MODELS=""
+HELIX_VERSION=""
 
 # Determine OS and architecture
 OS=$(uname -s | tr '[:upper:]' '[:lower:]')
@@ -45,8 +46,14 @@ case $ARCH in
     *) echo "Unsupported architecture: $ARCH"; exit 1 ;;
 esac
 
-# Determine latest release
-LATEST_RELEASE=$(curl -s ${PROXY}/latest.txt)
+# Determine version to install
+if [ -n "$HELIX_VERSION" ]; then
+    LATEST_RELEASE="$HELIX_VERSION"
+    echo "Using specified Helix version: $LATEST_RELEASE"
+else
+    LATEST_RELEASE=$(curl -s ${PROXY}/latest.txt)
+    echo "Using latest Helix version: $LATEST_RELEASE"
+fi
 
 # Set binary name
 BINARY_NAME="helix-${OS}-${ARCH}"
@@ -78,6 +85,7 @@ Options:
   --hf-token <token>       Specify the Hugging Face token for downloading models
   -y                       Auto approve the installation
   --extra-ollama-models    Specify additional Ollama models to download when installing the runner (comma-separated), for example "nemotron-mini:4b,codegemma:2b-code-q8_0"
+  --helix-version <version>  Override the Helix version to install (e.g. 1.4.0-rc4, defaults to latest stable)
 
 Examples:
 
@@ -198,6 +206,14 @@ while [[ $# -gt 0 ]]; do
             EXTRA_OLLAMA_MODELS="$2"
             shift 2
             ;;
+        --helix-version=*)
+            HELIX_VERSION="${1#*=}"
+            shift
+            ;;
+        --helix-version)
+            HELIX_VERSION="$2"
+            shift 2
+            ;;
         *)
             echo "Unknown option: $1"
             display_help
@@ -700,7 +716,7 @@ EOF"
     echo "│"
     echo "│ to start/upgrade Helix.  Helix will be available at $API_HOST"
     echo "│ This will take a minute or so to boot."
-    echo "└───────────────────────────────────────────────────────────────────────────"
+    echo "└───────────────────────���───────────────────────────────────────────────────"
 fi
 
 # Install runner if requested or in AUTO mode with GPU