[TIKA-4704] Implement pipes client shutdown in TikaGrpcServerImpl

[THausherr]

Added shutdown logic for pipes client in TikaGrpcServerImpl.

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[Copilot]

Pull request overview

This PR adds explicit shutdown/cleanup logic for the PipesClient used by the gRPC service implementation, so that underlying pipes resources are closed when the gRPC server is stopped.

Changes:

• Close pipesClient during TikaGrpcServerImpl.shutdown().
• Add logging around pipes client shutdown.

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Pull request overview

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Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

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[Copilot]

Server.awaitTermination(30, TimeUnit.SECONDS) returns after the timeout even if the server is still running; because the return value is ignored, postShutdown() (which closes pipesClient) may run while RPCs are still in-flight. Consider checking the boolean result and only closing pipesClient once termination has actually occurred (or call shutdownNow()/wait longer when the graceful shutdown times out).