✨(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- Helm sources are outdated.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.

.dockerignore

@@ -0,0 +1,36 @@
+# Python
+__pycache__
+*.pyc
+**/__pycache__
+**/*.pyc
+venv
+.venv
+
+# System-specific files
+.DS_Store
+**/.DS_Store
+
+# Docker
+docker compose.*
+env.d
+
+# Docs
+docs
+*.md
+*.log
+
+# Development/test cache & configurations
+data
+.cache
+.circleci
+.git
+.vscode
+.iml
+.idea
+db.sqlite3
+.mypy_cache
+.pylint.d
+.pytest_cache
+
+# Frontend
+node_modules