♻️(project) rename project from "publish" to "impress"

The repository was renamed to "impress" but the code was still
mentionning "publish".

src/backend/core/api/__init__.py

@@ -1,4 +1,4 @@
-"""publish core API endpoints"""
+"""Impress core API endpoints"""
 from django.conf import settings
 from django.core.exceptions import ValidationError
 

src/backend/core/api/permissions.py

@@ -1,4 +1,4 @@
-"""Permission handlers for the publish core app."""
+"""Permission handlers for the impress core app."""
 from django.core import exceptions
 
 from rest_framework import permissions

src/backend/core/api/serializers.py

@@ -1,4 +1,4 @@
-"""Client serializers for the publish core app."""
+"""Client serializers for the impress core app."""
 from django.db.models import Q
 from django.utils.translation import gettext_lazy as _