[improve][build] Upgrade gRPC to 1.84.0 - #26762

Motivation

Keep gRPC current with its stable release, including transport lifecycle and buffer-handling improvements.

Modifications

Upgrade the gRPC BOM and modules from 1.83.1 to 1.84.0 and update the server binary-license inventory.

Retain grpc-netty-shaded: Oxia client 0.9.5 directly references shaded Netty classes, so substituting grpc-netty would break its runtime linkage. The published grpc-netty-shaded 1.84.0 jar's version metadata confirms embedded Netty 4.2.16.Final, within the retained 4.2.x line. Pulsar's separately resolved Netty stays pinned at 4.2.18.Final.

Verifying this change

• Make sure that the change passes the CI checks.

help assemble sanityCheck checkBinaryLicense passed with configuration cache enabled, including main/test compilation and Checkstyle/Spotless.

All 11 ProcessRuntimeTest cases passed with retries disabled and no skips. Broader end-to-end RPC coverage remains for CI.

Does this pull request potentially affect one of the following parts:

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment