Test with Bazel 9 on both CI and BCR

.bazelversion

diff --git a/.bazelversion b/.bazelversion
index 8104cab..f7ee066 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-8.1.0
+9.0.0

.bcr/java/presubmit.yml

diff --git a/.bcr/java/presubmit.yml b/.bcr/java/presubmit.yml
index ed127b0..b58bdba 100644
--- a/.bcr/java/presubmit.yml
+++ b/.bcr/java/presubmit.yml
@@ -1,6 +1,6 @@
 matrix:
   platform: ["ubuntu2204", "macos", "macos_arm64"]
-  bazel: [7.x, 8.x, rolling]
+  bazel: [7.x, 8.x, 9.x, rolling]
 tasks:
   run_tests_unix:
     name: run tests

.bcr/proto/presubmit.yml

diff --git a/.bcr/proto/presubmit.yml b/.bcr/proto/presubmit.yml
index 2ee0e9c..23ac282 100644
--- a/.bcr/proto/presubmit.yml
+++ b/.bcr/proto/presubmit.yml
@@ -1,6 +1,6 @@
 matrix:
   platform: ["ubuntu2204", "macos", "macos_arm64", "windows"]
-  bazel: [7.x, 8.x, rolling]
+  bazel: [7.x, 8.x, 9.x, rolling]
 tasks:
   run_tests:
     name: build targets