Made consistent design for landing page and login. Landing page has all the text and design.

Added language support for english and german (swappable)

app/routes/main_routes.py

@@ -226,7 +226,8 @@ def build_save_point_query():
 
 @main_bp.route("/")
 def home():
-    return render_template("index.html")
+    initial_language = request.accept_languages.best_match(["de", "en"]) or "de"
+    return render_template("index.html", initial_language=initial_language)
 
 
 @main_bp.route("/dashboard")