Prevent OpenTelemetryDataSource constructor issues during config refresh by adding proxy

[rajeswari2904]

Fixes #13512:

• Addresses issue where Spring Boot configuration refresh (e.g., via Nacos) fails due to constructor/type errors with instrumented DataSource beans.
• Wraps the instrumented DataSource with a JDK dynamic proxy implementing only the DataSource interface.
• Proxy ensures Spring interacts only with the DataSource interface, avoiding exposure of implementation details (like OpenTelemetryDataSource).
• Prevents errors such as "ExistingValue must be an instance of com.zaxxer.hikari.HikariDataSource" during bean rebinding.
• Maintains compatibility with Spring’s configuration properties rebinding and refresh mechanisms.
• The proxy delegates all method calls to the underlying instrumented DataSource, preserving all functionality and telemetry.
• Adds in-code comments explaining the rationale for proxying the DataSource.
• Adds a test case to verify the DataSource proxying and configuration rebinding fix, ensuring that the solution is validated and regressions are prevented.

[linux-foundation-easycla]

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[otelbot-java-instrumentation]

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