deps: upgrade Go 1.24.13/1.25.7, protoc 33.5, and module dependencies (#917)

- Go minimum 1.24.12 → 1.24.13, toolchain go1.25.6 → go1.25.7 (Feb 4
security fixes)
- protoc 33.4 → 33.5, protoc-gen-go-grpc 1.6.0 → 1.6.1
- Update all Go module dependencies (go get -u -t ./...)
- Regenerate protobuf/grpc code

Co-authored-by: Claude Haiku 4.5 <noreply@anthropic.com>

internal/rpc/grpcclientidentity/example/pdu/grpcauth.pb.go

@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
 // 	protoc-gen-go v1.36.11
-// 	protoc        v6.33.4
+// 	protoc        v6.33.5
 // source: grpcauth.proto
 
 package pdu