fix(deps): update module google.golang.org/grpc to v1.78.0

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
google.golang.org/grpc	v1.77.0 -> v1.78.0

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Release Notes

grpc/grpc-go (google.golang.org/grpc)

v1.78.0: Release 1.78.0

Compare Source

Behavior Changes

• client: Reject target URLs containing unbracketed colons in the hostname in Go version 1.26+. (#​8716)
  • Special Thanks: @​neild

New Features

• stats/otel: Add backend service label to wrr metrics as part of A89. (#​8737)
• stats/otel: Add subchannel metrics (without the disconnection reason) to eventually replace the pickfirst metrics. (#​8738)
• client: Wait for all pending goroutines to complete when closing a graceful switch balancer. (#​8746)
  • Special Thanks: @​twz123

Bug Fixes

• transport/client : Return status code Unknown on malformed grpc-status. (#​8735)
• client: Add experimental.AcceptCompressors so callers can restrict the grpc-accept-encoding header advertised for a call. (#​8718)
  • Special Thanks: @​iblancasa
• xds: Fix a bug in StringMatcher where regexes would match incorrectly when ignore_case is set to true. (#​8723)
• xds/resolver:
  • Drop previous route resources and report an error when no matching virtual host is found.
  • Only log LDS/RDS configuration errors following a successful update and retain the last valid resource to prevent transient failures. (#​8711)
• client:
  • Change connectivity state to CONNECTING when creating the name resolver (as part of exiting IDLE).
  • Change connectivity state to TRANSIENT_FAILURE if name resolver creation fails (as part of exiting IDLE).
  • Change connectivity state to IDLE after idle timeout expires even when current state is TRANSIENT_FAILURE.
  • Fix a bug that resulted in OnFinish call option not being invoked for RPCs where stream creation failed. (#​8710)
• xdsclient: Fix a race in the xdsClient that could lead to resource-not-found errors. (#​8627)

Performance Improvements

• mem: Round up to nearest 4KiB for pool allocations larger than 1MiB. (#​8705)
  • Special Thanks: @​cjc25

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[renovate]

ℹ️ Artifact update notice

File name: go.mod

In order to perform the update(s) described in the table above, Renovate ran the go get command, which resulted in the following additional change(s):

• 2 additional dependencies were updated

Details:

Package	Change
google.golang.org/genproto/googleapis/api	v0.0.0-20251022142026-3a174f9686a8 -> v0.0.0-20251029180050-ab9386a59fda
google.golang.org/genproto/googleapis/rpc	v0.0.0-20251022142026-3a174f9686a8 -> v0.0.0-20251029180050-ab9386a59fda