add buildbuddy RBE config

.bazelrc

@@ -5,6 +5,12 @@ common --experimental_google_legacy_api # needed by protobuf
 # @rules_java
 common --experimental_rule_extension_api
 
+build:remote_buildbuddy --host_platform=@buildbuddy_toolchain//:platform
+build:remote_buildbuddy --platforms=@buildbuddy_toolchain//:platform
+build:remote_buildbuddy --extra_execution_platforms=@buildbuddy_toolchain//:platform
+build:remote_buildbuddy --crosstool_top=@buildbuddy_toolchain//:toolchain
+build:remote_buildbuddy --extra_toolchains=@buildbuddy_toolchain//:cc_toolchain
+
 # Shared configuration flags to build and test Bazel on RBE.
 build:remote_shared --remote_instance_name=projects/bazel-untrusted/instances/default_instance
 build:remote_shared --remote_executor=grpcs://remotebuildexecution.googleapis.com
@@ -52,8 +58,8 @@ build:windows --host_cxxopt=/std:c++17
 # Enable Java 21 language features
 build --java_runtime_version=21
 build --java_language_version=21
-build --tool_java_language_version=21
-build --tool_java_runtime_version=21
+build --tool_java_language_version=remotejdk_21
+build --tool_java_runtime_version=remotejdk_21
 
 # Fail if a glob doesn't match anything (https://github.com/bazelbuild/bazel/issues/8195)
 common --incompatible_disallow_empty_glob

WORKSPACE

@@ -0,0 +1,14 @@
+http_archive(
+    name = "io_buildbuddy_buildbuddy_toolchain",
+    sha256 = "baa9af1b9fcc96d18ac90a4dd68ebd2046c8beb76ed89aea9aabca30959ad30c",
+    strip_prefix = "buildbuddy-toolchain-287d6042ad151be92de03c83ef48747ba832c4e2",
+    urls = ["https://github.com/buildbuddy-io/buildbuddy-toolchain/archive/287d6042ad151be92de03c83ef48747ba832c4e2.tar.gz"],
+)
+
+load("@io_buildbuddy_buildbuddy_toolchain//:deps.bzl", "buildbuddy_deps")
+
+buildbuddy_deps()
+
+load("@io_buildbuddy_buildbuddy_toolchain//:rules.bzl", "buildbuddy")
+
+buildbuddy(name = "buildbuddy_toolchain")