Improve error handling in screenshot capture: return None for failures and add error message display in Gradio app

Update build workflow to target only linux/amd64 platform for Docker publishing

Refactor Dockerfile to streamline Chrome and ChromeDriver installation; set display port to avoid crashes

Add Chrome and ChromeDriver installation to Dockerfile; enhance screenshot functionality with improved options and logging

Enhance Dockerfile and screenshot functionality: create cache directories, set permissions, and initialize Chrome service for improved screenshot capture.

Add non-root user and configure cache directory in Dockerfile

Update app port in README from 8080 to 7860

Rename project to "capture-page-tools" and implement Gradio app for webpage screenshot capture

Initial commit