fix: build_linux.sh 添加 venv 降级机制，适配无 python3-venv 环境

build/build_linux.sh

@@ -12,12 +12,27 @@ if ! command -v python3 &> /dev/null; then
     echo "Error: python3 not found"; exit 1
 fi
 
-VENV_DIR="$PROJECT_ROOT/.venv_build"
-echo "Creating virtual environment: $VENV_DIR"
-python3 -m venv "$VENV_DIR"
-source "$VENV_DIR/bin/activate"
-pip install --upgrade pip
-pip install -r requirements.txt
+# ── 尝试 venv 隔离构建，失败则用系统环境 ──
+USE_VENV=false
+if python3 -m venv --help &>/dev/null; then
+    VENV_DIR="$PROJECT_ROOT/.venv_build"
+    if python3 -m venv "$VENV_DIR" 2>/dev/null; then
+        source "$VENV_DIR/bin/activate"
+        USE_VENV=true
+        echo "Using virtual environment"
+        pip install --upgrade pip -q
+        pip install -r requirements.txt -q
+    else
+        echo "Warning: venv creation failed, falling back to system Python"
+    fi
+else
+    echo "Warning: python3-venv not available, falling back to system Python"
+fi
+
+if [ "$USE_VENV" = false ]; then
+    pip install -r requirements.txt --break-system-packages -q 2>/dev/null || \
+        pip install -r requirements.txt -q 2>/dev/null || true
+fi
 
 echo "Cleaning previous builds..."
 rm -rf dist/ build/trulymem/ 2>/dev/null || true
@@ -25,13 +40,15 @@ rm -rf dist/ build/trulymem/ 2>/dev/null || true
 echo "================================"
 echo "Building TrulyMEM (TUI + Web embedded)"
 echo "================================"
-python -m PyInstaller --clean build/trulymem.spec --noconfirm
+python3 -m PyInstaller --clean build/trulymem.spec --noconfirm
 
 echo "================================"
 echo "===== Build Complete ====="
 echo "Binary: dist/TrulyMEM"
 ls -la dist/
 
-deactivate
-rm -rf "$VENV_DIR"
+if [ "$USE_VENV" = true ]; then
+    deactivate 2>/dev/null || true
+    rm -rf "$VENV_DIR"
+fi
 echo "Build finished successfully!"