feat: Improve browser task isolation and resource management

- Create isolated browser contexts for each task to prevent conflicts
- Replace global browser context with task-specific instances
- Add proper resource cleanup in finally blocks to prevent memory leaks
- Extract hardcoded values as constants for better maintainability
- Add comprehensive type hints throughout the codebase
- Improve error handling and logging
- Reorganize imports and improve code structure
- Update Dockerfile to use Playwright's bundled browser instead of custom Chrome
- Ensure each task runs in its own isolated environment with unique debugging ports
- Fix potential race conditions when multiple tasks access the same context

Author: michiosw

Dockerfile

@@ -13,6 +13,7 @@ RUN apt-get update -y && \
 # Install Python before the project for caching
 RUN uv python install 3.13
 
+
 WORKDIR /app
 RUN --mount=type=cache,target=/root/.cache/uv \
     --mount=type=bind,source=uv.lock,target=uv.lock \
@@ -35,8 +36,6 @@ RUN apt-get update && \
     tigervnc-tools \
     nodejs \
     npm \
-    chromium \
-    chromium-driver \
     fonts-freefont-ttf \
     fonts-ipafont-gothic \
     fonts-wqy-zenhei \
@@ -56,8 +55,7 @@ COPY --from=builder --chown=app:app /app /app
 ENV PATH="/app/.venv/bin:$PATH" \
     DISPLAY=:0 \
     CHROME_BIN=/usr/bin/chromium \
-    CHROMIUM_FLAGS="--no-sandbox --headless --disable-gpu --disable-software-rasterizer --disable-dev-shm-usage" \
-    CHROME_PATH="/usr/bin/chromium"
+    CHROMIUM_FLAGS="--no-sandbox --headless --disable-gpu --disable-software-rasterizer --disable-dev-shm-usage"
 
 # Combine VNC setup commands to reduce layers
 RUN mkdir -p ~/.vnc && \
@@ -69,6 +67,9 @@ RUN mkdir -p ~/.vnc && \
     chmod +x /app/boot.sh
 
 
+RUN playwright install --with-deps --no-shell chromium
+
+
 EXPOSE 8000
 
 ENTRYPOINT ["/bin/bash", "/app/boot.sh"]