chore: update .gitignore and requirements for development

- Added new entries to .gitignore to exclude temporary files and training input datasets, ensuring a cleaner repository.
- Included type stubs for psycopg2 in requirements-dev.txt to enhance type checking support for database interactions.
- Refactored the run_training_test.py script to implement a structured approach for loading and validating training input JSON files, improving the robustness of the training workflow.

.gitignore

@@ -247,4 +247,11 @@ sientia-module/
 .secrets
 .event.json
 
-models/
+models/
+.cursor
+openspec
+
+# Training smoke test: track JSON inputs, ignore local sample CSVs
+input_dataset.csv
+scripts/**/*.csv
+!scripts/inputs/