Encapsulate the non-critical code to prevent core disaster

[tangenta]

Enhancement

In #29925, we encountered an OOM issue caused by "printing a log". This is unexpected and the problems like this significantly decrease the stability and availability of TiDB.

Besides enhancing our tests, we had better mark the components/packages that are less critical, and encapsulate them with a proper recovery mechanism.

Less critical components:

• Logging
• Metrics
• Query feedback
• Memory tracker
• Telemetry
• Execdetails
• TopSQL
• Tracing

Possible recovery mechanisms:

• Golang's recover()
• Memory tracking
• Context canceller

Some refactoring work may be involved to decouple these components from the core.