fix install script again

install.sh

@@ -17,19 +17,41 @@ need_cmd() { command -v "$1" >/dev/null 2>&1; }
 
 install_neovim_linux() {
   # Install latest stable Neovim from GitHub releases (official tarball)
-  local tmp
+  local arch tmp url
+  arch="$(uname -m)"
   tmp="$(mktemp -d)"
   trap 'rm -rf "$tmp"' RETURN
 
-  local url="https://github.com/neovim/neovim/releases/download/v0.11.5/nvim-linux-x86_64.tar.gz"
+  case "$arch" in
+    x86_64|amd64) url="https://github.com/neovim/neovim/releases/latest/download/nvim-linux64.tar.gz" ;;
+    aarch64|arm64) url="https://github.com/neovim/neovim/releases/latest/download/nvim-linuxarm64.tar.gz" ;;
+    *)
+      echo "Unsupported architecture: $arch" >&2
+      return 1
+      ;;
+  esac
+
+  # -f: fail on HTTP errors, -L: follow redirects, -S: show errors
   curl -fL --retry 3 --retry-delay 1 -o "$tmp/nvim.tar.gz" "$url"
 
+  # quick sanity check (avoids "not in gzip format")
+  if ! tar -tzf "$tmp/nvim.tar.gz" >/dev/null 2>&1; then
+    echo "Downloaded file is not a valid gzip tarball: $url" >&2
+    echo "First bytes:" >&2
+    head -c 200 "$tmp/nvim.tar.gz" | sed -e 's/[^[:print:]\t]/./g' >&2
+    return 1
+  fi
+
   sudo rm -rf /opt/nvim
   sudo mkdir -p /opt
   sudo tar -C /opt -xzf "$tmp/nvim.tar.gz"
-  sudo mv /opt/nvim-linux64 /opt/nvim
 
-  # Ensure /usr/local/bin exists and symlink nvim
+  # tarball extracts to /opt/nvim-linux64 or /opt/nvim-linuxarm64
+  local extracted
+  extracted="$(tar -tzf "$tmp/nvim.tar.gz" | head -n1 | cut -d/ -f1)"
+  sudo mv "/opt/$extracted" /opt/nvim
+
+  sudo mkdir -p /usr/local/bin
   sudo ln -sf /opt/nvim/bin/nvim /usr/local/bin/nvim
 }