API for hackathons [fast track]

[r0wdy1]

Provide API for the service that can make zkBob transactions via a custodial wallet. The idea is to let teams at hackathons use private txns in their projects.

• [x] new accounts map to relayer app
• [x] Accounts must contain libxkbob-rs UserAccount and be stored in the persistence layer ( tree and txs)
• [x] auxiliary storage for history to account
• [x] #47
• [x] service to process signup requests, which returns unique API_KEY
• [x] list accounts service
• [x] service to sync an account / all accounts
• [x] #48
• [x] generate address
• [x] #49
• [x] #50
• [x] #51
• optimistic state support ( moved to a separate issue)
• [x] postman
• [x] swagger

[akolotov]

I have prepared description of the service in form of user stories here: https://blockscout.notion.site/Remote-prover-custodial-wallet-e8b812a349224c0ab78aa844ea209fca

[ulyanas]

Need

• test app
• admin access
• docs ETA - 2d

[ulyanas]

Testing - need performance testing