Docker and Docker-Compose Refactor

[1Solon]

This PR refactors the existing Dockerfile with:

• a multi-stage-build
• layer caching
• rootless containers

( Now you can add rootless container as another security buzzword! ;> )

Additionally, I've changed the docker-compose to take advantage of the above- and also included some volume configuration, in particular:

  volumes:
      # Persist app data between container restarts
      - app-data:/app
      # Mount saves and config for easy access/editing outside the container
      - ./saves:/app/saves:rw
      - ./UIMod/config:/app/UIMod/config:rw
      - ./UIMod/tls:/app/UIMod/tls:rw

Including the volume (and the mount overrides) allows us to maintain persistence between restarts, and also maintains performance (mounts are notorious for killing file i/o)

Changes

• added Github CodeQL
• (frontend) upd. dependencies and rm electron entirely
• refactor: update Dockerfile and compose.yml with rootless containers and multi-stage build process

[Copilot]

Pull Request Overview

This PR refactors the Docker and Docker-Compose setup to improve security, performance, and maintainability. It introduces a multi-stage build process with layer caching optimization and implements rootless containers for enhanced security.

• Removes Electron desktop application entirely and associated dependencies
• Implements multi-stage Docker build with separate frontend and Go compilation stages
• Adds GitHub CodeQL workflow for security analysis

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
frontend/package.json	Removes Electron dependencies and build scripts, bumps version to v5.6.4
frontend/main.cjs	Complete removal of Electron main process file (458 lines deleted)
compose.yml	Adds named volumes for data persistence and additional mount points for configuration
Dockerfile	Refactored to multi-stage build with rootless user, separate frontend/Go build stages
.github/workflows/codeql.yml	Adds GitHub CodeQL security analysis workflow for Go and JavaScript

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[1Solon]

Whoops, I did EXACTLY what you told me not to, let me remake that :P