feat(bqjdbc): Per connection logs - Add BigQueryJdbcMdc

[Neenu1995]

Implements BigQueryJdbcMdc using an InheritableThreadLocal design and corresponding unit tests for verfication.

[gemini-code-assist]

Code Review

This pull request introduces BigQueryJdbcMdc, a lightweight MDC implementation for the BigQuery JDBC driver using InheritableThreadLocal. Several critical architectural issues were identified: the dynamic creation of InheritableThreadLocal instances per connection is a significant anti-pattern that can lead to memory exhaustion; the static maps hold strong references to BigQueryConnection objects without a removal mechanism, causing memory leaks; and the global getConnectionId method suffers from O(N) complexity and non-deterministic behavior when multiple connections are present on the same thread.

[logachev]

Why using MDC if BigQueryConnection object is available? We can add public connectionId property to the BigQueryConnection instead.

[Neenu1995]

But then we don't have a way to track different connection IDs in multiple threads.

The MDC here keeps track of different connection instances and it's corresponding connection ID and thread. This is cross verified when a LOG message comes in and redirected to the appropriate log file.