Improve Docker build security and efficiency for frontend

[Nefrit0n]

Summary

This PR improves the Docker build configuration for the frontend application by implementing proper file ownership handling and adding a .dockerignore file to optimize build context.

Key Changes

• File ownership in COPY commands: Added --chown=node:node flag to all COPY instructions in both development and production build stages. This ensures files are owned by the node user rather than root, improving security and consistency with the USER node directive.
• Added .dockerignore file: Created a .dockerignore file to exclude unnecessary files and directories (node_modules, .vite, dist, .git, *.md) from the Docker build context, reducing build time and image size.

Implementation Details

• The --chown flag is applied to both package dependency files and application source code copies
• This change applies to both the development stage and the production build stage in the multi-stage Dockerfile
• The .dockerignore exclusions prevent redundant copying of build artifacts, dependencies, and documentation that don't need to be in the container

https://claude.ai/code/session_012GkEL9VGqN4tT4uFJuEjq1

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