Prefetch: Add sepolicy to control prefetch properties

1: Add prefetch tunable property
2: Default path to store the prefetch record is in /metadata/prefetch/
3: Add policy to control the service
4: Allow init to start/stop the service

Bug: 362507272
Test: Test prefetch record/replay with enforcing mode
Change-Id: I55cbf4f2110da298a8d7df52daad08eaedebd061
Signed-off-by: Akilesh Kailash <akailash@google.com>
diff --git a/private/file.te b/private/file.te
index 559b0fe..4ef8d55 100644
--- a/private/file.te
+++ b/private/file.te
@@ -224,6 +224,9 @@
 # /metadata/tradeinmode files
 type tradeinmode_metadata_file, file_type;
 
+# /metadata/prefetch files
+type prefetch_metadata_file, file_type;
+
 # Types added in 202504 in public/file.te
 until_board_api(202504, `
     type binderfs_logs_transactions, fs_type;