Add Russian translations for mineral property values

- Add properties_ru JSON field to store translated category, crystal_system,
  luster, streak, specific_gravity, color_description
- Add translate_minerals management command using deep-translator (Google
  Translate), with a hard-coded dictionary for crystal systems
- Template: show translated values in RU mode, fall back to English if missing
- Add deep-translator to requirements.txt

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

dailystone/migrations/0003_mineral_properties_ru.py

@@ -0,0 +1,16 @@
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('dailystone', '0002_add_russian_fields'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='mineral',
+            name='properties_ru',
+            field=models.JSONField(blank=True, default=dict),
+        ),
+    ]