[INS-425] Updated google.golang.org/grpc v1.78.0 --> v1.79.3

[MuneebUllahKhan222]

Description:

This PR updates the grpc Go package from version v1.78.0 to v1.79.3 to address a critical security vulnerability identified in the older version reported by dependabot here.

Checklist:

• Tests passing (make test-community)?
• Lint passing (make lint this requires golangci-lint)?

---

Note

Medium Risk
Primarily a dependency-only change, but it updates core RPC/telemetry libraries (grpc, opentelemetry, envoy protos) which could impact runtime behavior and compatibility if any gRPC-based integrations exist.

Overview
Upgrades google.golang.org/grpc from v1.78.0 to v1.79.3 in go.mod/go.sum to incorporate security and bugfix updates.

Also refreshes related transitive dependencies, including go.opentelemetry.io/otel v1.38.0 → v1.39.0, github.com/envoyproxy/protoc-gen-validate v1.2.1 → v1.3.0, and updated Envoy/xDS module versions reflected in go.sum.

^{Written by Cursor Bugbot for commit 141f601. This will update automatically on new commits. Configure here.}