add LLM configuration and backend management components with automated setup scripts

scripts/setup-llama.sh

@@ -31,10 +31,39 @@ download_and_extract() {
 
   if [[ ! -x "$dest/llama-server" ]]; then
     echo "   XX   llama-server was not found after extracting $asset" >&2
-    exit 1
+    return 1
   fi
 }
 
+download_and_extract_optional() {
+  local asset="$1"
+  local dest="$2"
+  local reason="$3"
+
+  if [[ -x "$dest/llama-server" ]]; then
+    echo "   OK   optional llama.cpp backend already ready: $dest"
+    return 0
+  fi
+
+  if download_and_extract "$asset" "$dest"; then
+    return 0
+  fi
+
+  echo "   !!   Skipping optional llama.cpp backend for $reason ($asset)" >&2
+  rm -rf "$dest"
+  return 0
+}
+
+has_command() {
+  command -v "$1" >/dev/null 2>&1
+}
+
+has_linux_gpu_vendor() {
+  local vendor="$1"
+  [[ -d /sys/bus/pci/devices ]] || return 1
+  grep -Ril "$vendor" /sys/bus/pci/devices/*/vendor >/dev/null 2>&1
+}
+
 if [[ "$PLATFORM" == "Darwin" ]]; then
   if [[ "$ARCH" == "arm64" ]]; then
     download_and_extract "llama-$RELEASE-bin-macos-arm64.tar.gz" "$APP_DIR/llm-backend/mac/arm64"
@@ -46,6 +75,15 @@ elif [[ "$PLATFORM" == "Linux" ]]; then
     download_and_extract "llama-$RELEASE-bin-ubuntu-vulkan-arm64.tar.gz" "$APP_DIR/llm-backend/linux/vulkan"
     download_and_extract "llama-$RELEASE-bin-ubuntu-arm64.tar.gz" "$APP_DIR/llm-backend/linux/cpu"
   else
+    if has_command nvidia-smi || has_linux_gpu_vendor "0x10de"; then
+      download_and_extract_optional "llama-$RELEASE-bin-ubuntu-cuda-12.4-x64.tar.gz" "$APP_DIR/llm-backend/linux/cuda" "NVIDIA CUDA acceleration"
+    fi
+    if has_command rocminfo || has_linux_gpu_vendor "0x1002"; then
+      download_and_extract_optional "llama-$RELEASE-bin-ubuntu-rocm-x64.tar.gz" "$APP_DIR/llm-backend/linux/rocm" "AMD ROCm acceleration"
+    fi
+    if has_linux_gpu_vendor "0x8086"; then
+      download_and_extract_optional "llama-$RELEASE-bin-ubuntu-sycl-fp32-x64.tar.gz" "$APP_DIR/llm-backend/linux/sycl" "Intel SYCL acceleration"
+    fi
     download_and_extract "llama-$RELEASE-bin-ubuntu-vulkan-x64.tar.gz" "$APP_DIR/llm-backend/linux/vulkan"
     download_and_extract "llama-$RELEASE-bin-ubuntu-x64.tar.gz" "$APP_DIR/llm-backend/linux/cpu"
   fi