feat: build ink web app in ci

[ink-victor]

Changes:

• Set up Dockerfile for ink-web-app
• Set up CI to build, push and deploy updates on pushes to main, ops/preview-1 and ops/preview-2
• Set up schema for our environment variables to make them predictable
• Improved .env.example with a better structure
• Created scripts/generate-dummy-dotenv.sh script to populate .env.production for CI jobs like lint and format that do not need the real secrets
• Updated README.md with better content
• Replaced ink-landingpage Sentry project with new ink-web-app project
• Fixed sanitize/dompurify errors

Notes:

• app-ink-web-app is going to be updated on feat/ink-web-app branch. The main reason being that main is protected and required signed commits.