feat: add contained, persistent calculator

app/apps/common/templatetags/formats.py

@@ -0,0 +1,17 @@
+from django import template
+from django.utils.formats import get_format
+
+
+register = template.Library()
+
+
+@register.simple_tag
+def get_thousand_separator():
+    print(get_format("THOUSAND_SEPARATOR"))
+    return get_format("THOUSAND_SEPARATOR")
+
+
+@register.simple_tag
+def get_decimal_separator():
+    print(get_format("DECIMAL_SEPARATOR"))
+    return get_format("DECIMAL_SEPARATOR")