Restructure: site/ with modular code, matching Nubes Flask convention

site/routes/main.py

@@ -0,0 +1,23 @@
+"""Главная страница — blueprint."""
+
+from flask import Blueprint, current_app, render_template
+
+from api.http_client import HttpClient
+from operations.get_instances import get_organization
+
+bp = Blueprint("main", __name__)
+
+
+@bp.route("/")
+def index():
+    org = None
+    error = None
+    try:
+        client = HttpClient(
+            current_app.config["NUBES_API_ENDPOINT"],
+            current_app.config["NUBES_API_TOKEN"],
+        )
+        org = get_organization(client)
+    except Exception as e:
+        error = str(e)
+    return render_template("index.html", organization=org, error=error)