Sync too many retries

- When an one-shot sync with app-standby exempt fails too many times in a row,
drop the "exempt from app-standby" flag.

- Also obtain some constants from global settings so we can change them
in CTS.

Bug: 72443754
Test: Manual test (CTS WIP)

Change-Id: Ibdbb348a7ff26a0be04b8f2c256e1f6ead39907d

core/java/android/provider/Settings.java

@@ -10504,6 +10504,16 @@ public final class Settings {
          */
         public static final String BATTERY_STATS_CONSTANTS = "battery_stats_constants";
 
+        /**
+         * SyncManager specific settings.
+         *
+         * <p>
+         * Type: string
+         * @hide
+         * @see com.android.server.content.SyncManagerConstants
+         */
+        public static final String SYNC_MANAGER_CONSTANTS = "sync_manager_constants";
+
         /**
          * Whether or not App Standby feature is enabled. This controls throttling of apps
          * based on usage patterns and predictions.