fix(manage): use account-scoped device sync and remove mock device source

Preserve Manage device state across resume while preventing cross-account cache leaks by tracking synced user IDs and clearing stale local device data on account changes. Replace the mock device remote data source with Apollo-backed API queries/mutations using me.locations so Manage only shows devices belonging to the authenticated user.

Made-with: Cursor

sdk/src/main/graphql/DeviceAction.graphql

@@ -0,0 +1,5 @@
+mutation DeviceAction($input: SendAction) {
+  deviceAction(input: $input) {
+    success
+  }
+}