fix: robust node.js version parsing in installers

Improved Node.js version check logic to handle prefixed version strings and avoid brittle cut commands. Verified with multiple version formats including v24.11.1.

install-claude-code.sh

@@ -108,14 +108,21 @@ check_nodejs() {
         exit 1
     fi
 
-    local node_version=$(node -v | cut -d'v' -f2 | cut -d'.' -f1)
-    if [ "$node_version" -lt 18 ]; then
-        log_error "Node.js version $node_version is too old!"
-        echo "Node.js 18 or newer is required."
+    local node_full_version=$(node -v 2>&1)
+    local node_version=$(echo "$node_full_version" | grep -oE '[0-9]+' | head -n1)
+    
+    if [ -z "$node_version" ]; then
+        log_error "Could not parse Node.js version from: $node_full_version"
         exit 1
     fi
 
-    log_success "Node.js $(node -v) found"
+    if [ "$node_version" -lt 18 ]; then
+        log_error "Node.js version $node_version is too old!"
+        echo "Node.js 18 or newer is required. Found: $node_full_version"
+        exit 1
+    fi
+
+    log_success "Node.js $node_full_version found"
 }
 
 check_claude_code_installed() {