Own legacy platform services on Web and Android

docs/modernization/tasks.md

@@ -78,6 +78,11 @@ Completed, blocked, and superseded task history moved to
   the queue is now ordered by code movement instead.
 
 Current slice:
+- `webgl/src/main.cpp` now binds an owned legacy `PlatformServices` instance
+  instead of reading the process-global fallback directly during `StartApp()`.
+- `android/src/cpp/main.cpp` now binds a function-lifetime owned legacy
+  `PlatformServices` instance in `android_main()`, replacing the direct bind to
+  the process-global fallback accessor.
 - `src/platform_legacy/legacy_platform_services.*` now exposes an ownable
   `create_platform_services()` entrypoint while keeping the fallback singleton
   for non-migrated platforms.