fix(cistech-tunnel): add software rendering support for Qt WebEngine

- Add QT_QUICK_BACKEND=software, LIBGL_ALWAYS_SOFTWARE=1
- Add mesa-utils, libgl1-mesa-dri for llvmpipe software renderer
- Add missing xcb libraries (libxcb-render0, libxcb-shm0, etc.)
- Use --use-gl=swiftshader in chromium flags

apps/cistech-tunnel/build/Dockerfile

@@ -67,17 +67,26 @@ RUN apt-get update && apt-get install -y \
     libxkbcommon0 \
     libxkbcommon-x11-0 \
     fonts-liberation \
-    # EGL/GL for PyQt6 WebEngine
+    # EGL/GL for PyQt6 WebEngine + software rendering
     libegl1 \
     libgl1 \
     libopengl0 \
-    # XCB libraries for Qt6
+    libdbus-1-3 \
+    mesa-utils \
+    libgl1-mesa-dri \
+    # XCB libraries for Qt6 (complete set)
+    libxcb1 \
     libxcb-cursor0 \
     libxcb-icccm4 \
     libxcb-image0 \
     libxcb-keysyms1 \
+    libxcb-render0 \
     libxcb-render-util0 \
+    libxcb-shm0 \
+    libxcb-xfixes0 \
     libxcb-xinerama0 \
+    libxcb-randr0 \
+    libxcb-glx0 \
     libxcb-shape0 \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*