[Thread] initial Thread network service

This commit sets up the initial Thread network service for the
Android Thread feature which allows an Android device to create
a Thread network and being a Border Router.

See https://www.threadgroup.org/What-is-Thread for background of
Thread.

See b/235016403 for the Android Thread feature request.

Test: lunch aosp_cf_x86_64_tv-userdebug
      m && launch_cvd
      atest CtsThreadNetworkTestCases
Bug: 262683651
Change-Id: Ie1bb23084531f67165ec068ea3ca39592dbc01d1
diff --git a/thread/TEST_MAPPING b/thread/TEST_MAPPING
new file mode 100644
index 0000000..17a74f6
--- /dev/null
+++ b/thread/TEST_MAPPING
@@ -0,0 +1,9 @@
+{
+  // TODO (b/297729075): graduate this test to presubmit once it meets the SLO requirements.
+  // See go/test-mapping-slo-guide
+  "postsubmit": [
+    {
+      "name": "CtsThreadNetworkTestCases"
+    }
+  ]
+}