feat: add CI/CD workflow and update documentation

- Add .gitea/workflows/docker-publish.yaml for automated builds
- Configure workflow to trigger on main branch
- Update README.md with deployment instructions
- Update START-HERE.md with session context

This enables automatic Docker image builds tagged as :latest and :<sha>
when pushing to main branch.

Dockerfile

@@ -1,5 +1,5 @@
 # Use official Bun image
-# ***NEVER FORGET THE PRINCIPLES***
+# ***NEVER FORGET THE PRINCIPLES RULES***
 FROM oven/bun:1.3-alpine AS base
 
 # Set working directory