[Feature] Documentation for development setup

## Summary

This PR improves the local development setup experience by adding Docker Compose and Makefile for streamlined setup.

## Changes

- **Added `docker-compose.yml`**: for one-command PostgreSQL database setup
- **Added `Makefile`**: Convenient shortcuts for common dev tasks (\`make setup\`, \`make dev\`, etc.)
- **Updated `README.md`**: Quick development setup instructions using Make
-
- **Added**: RDkit installation pain point documentation
- **Fixed**: Made Java feature properly dependent

## Why these changes?

The application uses PostgreSQL-specific features (\`ArrayField\`) and requires an anonymous user created by the bootstrap command. This PR makes the setup process trivial for new developers:

```bash
cp .env.local.example .env
make setup  # Starts DB, runs migrations, bootstraps data
make dev    # Starts development server
```

Java fix:
Moved global Java import to inline to avoid everyone having to configure the Java path.

Numerous changes to view and settings.
- Applied ruff-formatting

## Testing

Verified complete setup from scratch works with:
- PostgreSQL running in Docker
- All migrations applied
- Bootstrap data loaded successfully
- Anonymous user created
- The development server starts correctly.

Co-authored-by: Tobias O <tobias.olenyi@tum.de>
Co-authored-by: Tobias O <tobias.olenyi@envipath.com>
Co-authored-by: Liam <62733830+limmooo@users.noreply.github.com>
Reviewed-on: enviPath/enviPy#143
Reviewed-by: jebus <lorsbach@envipath.com>
Reviewed-by: liambrydon <lbry121@aucklanduni.ac.nz>
Co-authored-by: t03i <mail+envipath@t03i.net>
Co-committed-by: t03i <mail+envipath@t03i.net>

.env.local.example

@@ -0,0 +1,22 @@
+# Django settings
+SECRET_KEY='a-secure-secret-key-for-development'
+DEBUG=True
+ALLOWED_HOSTS=*
+
+# Database settings (using PostgreSQL for local development)
+POSTGRES_USER=postgres
+POSTGRES_PASSWORD=postgres
+POSTGRES_DB=envipath
+POSTGRES_SERVICE_NAME=localhost
+POSTGRES_PORT=5432
+
+# Celery settings
+CELERY_BROKER_URL='redis://localhost:6379/0'
+CELERY_RESULT_BACKEND='redis://localhost:6379/0'
+FLAG_CELERY_PRESENT=False
+
+# Other settings
+LOG_LEVEL='INFO'
+SERVER_URL='http://localhost:8000'
+PLUGINS_ENABLED=True
+EP_DATA_DIR='data'