Update googletest to 1.18.0 and SIMDe to 0.8.2.

Googletest 1.18 asks for CMake 3.13 or newer, so configuring the tests no longer warns that CMake compatibility below 3.10 is deprecated.

Co-authored-by: Cursor <cursoragent@cursor.com>

test/googletest/fake_fuchsia_sdk.bzl

@@ -0,0 +1,61 @@
+"""Provides a fake @fuchsia_sdk implementation that's used when the real one isn't available.
+
+GoogleTest can be used with the [Fuchsia](https://fuchsia.dev/) SDK. However,
+because the Fuchsia SDK does not yet support bzlmod, GoogleTest's `MODULE.bazel`
+file by default provides a "fake" Fuchsia SDK.
+
+To override this and use the real Fuchsia SDK, you can add the following to your
+project's `MODULE.bazel` file:
+
+    fake_fuchsia_sdk_extension =
+    use_extension("@com_google_googletest//:fake_fuchsia_sdk.bzl", "fuchsia_sdk")
+    override_repo(fake_fuchsia_sdk_extension, "fuchsia_sdk")
+
+NOTE: The `override_repo` built-in is only available in Bazel 8.0 and higher.
+
+See https://github.com/google/googletest/issues/4472 for more details of why the
+fake Fuchsia SDK is needed.
+"""
+
+def _fake_fuchsia_sdk_impl(repo_ctx):
+    for stub_target in repo_ctx.attr._stub_build_targets:
+        stub_package = stub_target
+        stub_target_name = stub_target.split("/")[-1]
+        repo_ctx.file("%s/BUILD.bazel" % stub_package, """
+filegroup(
+    name = "%s",
+)
+""" % stub_target_name)
+
+fake_fuchsia_sdk = repository_rule(
+    doc = "Used to create a fake @fuchsia_sdk repository with stub build targets.",
+    implementation = _fake_fuchsia_sdk_impl,
+    attrs = {
+        "_stub_build_targets": attr.string_list(
+            doc = "The stub build targets to initialize.",
+            default = [
+                "pkg/fdio",
+                "pkg/syslog",
+                "pkg/zx",
+            ],
+        ),
+    },
+)
+
+_create_fake = tag_class()
+
+def _fuchsia_sdk_impl(module_ctx):
+    create_fake_sdk = False
+    for mod in module_ctx.modules:
+        for _ in mod.tags.create_fake:
+            create_fake_sdk = True
+
+    if create_fake_sdk:
+        fake_fuchsia_sdk(name = "fuchsia_sdk")
+
+    return module_ctx.extension_metadata(reproducible = True)
+
+fuchsia_sdk = module_extension(
+    implementation = _fuchsia_sdk_impl,
+    tag_classes = {"create_fake": _create_fake},
+)