WIP: feat(bridge): provide a way to check the bridge application's health

[moreal]

📓 Ways

I thought there are two ways to implement it:

1. Open the health-check endpoint and check it with other uptime checker services (e.g. uptime robot).
2. Create a shared volume on docker-compose and the

😟 My worries

When I made planetarium/NineChronicles.EthBridge, I hope that it doesn't receive any inbound requests because of security issues. I thought every security exception occurred from unexpected input. The reason to use SQLite was to restrict modifying the database directly from outside users, not bridge.

Though I imagined a machine working without humans' touch, it failed because of my mistakes like bugs, not enough testing, no understanding of how to manage assets in the blockchain scene, and not considering operations.

Anyway, the bridge application was a product of planetarium, it should check how many WNCG it earned and configure the properties like taxes and the limitation to exchange NCG. Maybe outside databases like DynamoDB were suited more than SQLite because all transactions' process results must be maintained.