✨(project) Django boilerplate

This commit introduces a boilerplate inspired by https://github.com/numerique-gouv/impress.
The code has been cleaned to remove unnecessary Impress logic and dependencies.

Changes made:
- Removed Minio, WebRTC, and create bucket from the stack.
- Removed the Next.js frontend (it will be replaced by Vite).
- Cleaned up impress-specific backend logics.

The whole stack remains functional:
- All tests pass.
- Linter checks pass.
- Agent Connexion sources are already set-up.

Why clear out the code?

To adhere to the KISS principle, we aim to maintain a minimalist codebase. Cloning Impress
allowed us to quickly inherit its code quality tools and deployment configurations for staging,
pre-production, and production environments.

What’s broken?
- The tsclient is not functional anymore.
- Some make commands need to be fixed.
- Helm sources are outdated.
- Naming across the project sources are inconsistent (impress, visio, etc.)
- CI is not configured properly.

This list might be incomplete. Let's grind it.

src/backend/core/factories.py

@@ -0,0 +1,25 @@
+# ruff: noqa: S311
+"""
+Core application factories
+"""
+from django.conf import settings
+from django.contrib.auth.hashers import make_password
+
+import factory.fuzzy
+from faker import Faker
+
+from core import models
+
+fake = Faker()
+
+
+class UserFactory(factory.django.DjangoModelFactory):
+    """A factory to random users for testing purposes."""
+
+    class Meta:
+        model = models.User
+
+    sub = factory.Sequence(lambda n: f"user{n!s}")
+    email = factory.Faker("email")
+    language = factory.fuzzy.FuzzyChoice([lang[0] for lang in settings.LANGUAGES])
+    password = make_password("password")