test: validate all benchmark scenarios and stress runs for all DI adapters

- Successfully executed all scenarios (register, chain, asyncChain, named, override, etc) for Cherrypick, GetIt, and Riverpod
- Verified correct integration of fully generic DIAdapter & universalRegistration architecture
- Ensured type-safety in all setup/registration flows after complete refactor
- All benchmarks run and pass under stress/load params for each DI adapter

benchmark_di/lib/scenarios/universal_scenario.dart

@@ -0,0 +1,13 @@
+/// Enum to represent which scenario is constructed for the benchmark.
+enum UniversalScenario {
+  /// Single registration.
+  register,
+  /// Chain of dependencies.
+  chain,
+  /// Named registrations.
+  named,
+  /// Child-scope override scenario.
+  override,
+  /// Asynchronous chain scenario.
+  asyncChain,
+}