perf: optimize startup, database, and ui rendering (#405)

* perf: optimize startup, database, and ui rendering

* fix(#405): address code review feedback

* test: wait for async prefs initialization to prevent coroutine leaks

* test: stub mockViewModel.streamingState in ChatScreenTest to prevent ClassCastException on Android

.gitignore

@@ -19,3 +19,8 @@ $PWD/
 
 ktlint
 .hermes/plans/
+
+# Local workspace artifacts and logs
+*.py
+.kotlin/
+