feat: updated readme

README.md

@@ -105,3 +105,22 @@ After successful upgrade:
 - Your account gains full admin privileges
 - No new token is generated (admin now exists)
 - Trying to upgrade another account will fail (token is spent)
+
+## Data Model
+
+The application schema is defined with Drizzle ORM under `src/lib/model/`. Below are short descriptions of the available schema files and what they represent; see the files themselves for full structure.
+
+- `auth-schema.ts` — user and authentication-related tables: `user` (accounts and admin flag), `session` (auth sessions), `account` (external OAuth/accounts), and `verification` (verification tokens).
+- `dataset.ts` — `dataset` table: logical collections of audio items and dataset-level metadata.
+- `dataset_entry.ts` — `dataset_entry` table: individual audio metadata rows belonging to a dataset (file path, speaker id, dialect labels, metrics, etc.).
+- `experiment.ts` — `experiment` table: admin-configured annotation experiments referencing a dataset and experiment settings.
+- `experiment_calibration.ts` — `experiment_calibration` table: ordered calibration items (audio + labels) used when `calibrationEnabled` is set on an experiment.
+- `annotation.ts` — `annotation` table: annotator responses for dataset entries within experiments (rating, confidence, chosen dialect label); includes a uniqueness constraint to avoid duplicate annotations per user/item/experiment.
+- `participant.ts` — `participant` table: links users to experiments and stores onboarding/calibration answers per participant.
+
+When you change the model files in `src/lib/model/`, run the migration steps in "Modifying the Data Model" to generate and push migrations.
+
+## Logical Steps: Creating and publishing an experiment
+1. Create a new dataset containing all Samples. Can also be created by duplicating an already present dataset.
+2. Create a new experiment using a dataset.
+3. Publish the experiment.