Tracking Issues of OpenDAL Observability

[Xuanwo]

We have moved all our observability code into layers: https://opendal.databend.rs/opendal/layers/index.html

But we didn't track the structs returned by our APIs like reader and writer.

This issue is used to track this problem.

Tasks

Logging

• [ ] Add log for Reader returned by read
• [ ] Add log for Writer returned by write
• [ ] Add log for DirStreamer returned by list

Tracing

• [ ] Add trace for Reader returned by read
• [ ] Add trace for Writer returned by write
• [ ] Add trace for DirStreamer returned by list

Metrics

• [ ] Add metrics for Reader returned by read
• [ ] Add metrics for Writer returned by write
• [ ] Add metrics for DirStreamer returned by list