Pin abseil-cpp to 20260107.1 for compatibility with Bazel < 9.1

Author: BYVoid

MODULE.bazel

@@ -1,6 +1,10 @@
 module(name = "clickhouse_cpp", version = "2.6.1")
 
-bazel_dep(name = "abseil-cpp", version = "20260526.0")
+# Pinned to 20260107.1, the last version that declares
+# `compatibility_level = 1`, so that the module remains importable on
+# Bazel < 9.1 whose bazel_tools also depends on a level-1 abseil-cpp.
+# See PR discussion; the attribute is a no-op from Bazel 9.1.0 onwards.
+bazel_dep(name = "abseil-cpp", version = "20260107.1")
 bazel_dep(name = "bazel_skylib", version = "1.9.0")
 bazel_dep(name = "boringssl", version = "0.20260526.0")
 bazel_dep(name = "cityhash", version = "1.0.2")