Build backend

[shinaBR2]

Updated: due to the limit of the Google Cloud for my region, so I will go with Cloud Functions first.

Regardless of the Cloud Run/Cloud Functions and what the network layer is, the logic is still the same.

Set up a new backend using Cloud Run and Cloud Functions.
When to use Cloud Run: for regular HTTP requests
When to use Cloud Functions: event-driven with Firebase Authentication, Firestore's event, etc.

Using the current api workspace.

Problems: Firebase functions still do not offer an official way to deal with the monorepo. Here is a good example to get started with: https://github.com/Hacksore/turborepo-firebase-example

References:

• Examples: Add Firebase functions vercel/turbo#1121
• https://github.com/vercel/turbo/pull/1966/files#diff-6a98014974969000909161206b907a73e1b6d1af1ac88abf50de768ea847d392
• https://stackoverflow.com/questions/61015842/deploying-to-firebase-functions-with-a-monorepo
• Support mono-repos in deployment firebase/firebase-tools#653
• Functions deployment fails when firebase-functions has been hoisted by a monorepo manager like yarn/workspaces or lerna firebase/firebase-functions#172