Add Database Log

[dan-tang-ssd]

This PR is submitted to help resolving issue for exchange rate retrieval.

This PR contains below changes:

1. Add log message in database level to trace program executed by schedule job and queue
2. Add configuration in .env, make it flexible to turn on / turn off database log feature

---

Testing in local env:

When QUEUE_CONNECTION=sync

• only first 5 currencies exchange rate retrieved (33 * 5 = 165 records).
• no new records in jobs table

When QUEUE_CONNECTION=database

• system_logs table is empty
• jobs table is empty
• at the beginning, handle first 5 currencies
• after each minute, handled another 5 currencies
• finally 33 currencies exchange rate data retrieved (33 * 33 = 1089)

---

Possible casue in live env:

• 1650 jobs accumulated (1650 / 33 = 50 days), we may need to clear all jobs before deploying this PR

Screen shot:

[what-the-diff[bot]]

PR Summary

• Added Logging Level to the Environment Example File This makes it easier for those replicating the environment to preset the log levels - reducing noise and focusing on errors only.

• Integrated DB Log Service Into the GetExchangeRates Functionality The database log system now records details of the process to fetch exchange rates for a specific day. It logs when the process starts, ends, and even when a task for a specific currency and date is dispatched.

• Integrated DB Log Service Into the GetOneDayExchangeRates Functionality Several log entries have been added to create, retry and handle methods of this functionality. This helps in tracing the functionality's flow, records when errors occur, and keeps track of how many exchange rate records are created each time.

• System Log Model and DB Log Service We've added a new model to handle system logs, and a DB log service to interact with this model. This would provide a uniform way to handle log entries in our system.

• Applied Database Migration A new migration file was added to create the system logs table in the database. Empowering us to record and manage log entries directly from our application.