feat: Web-GUI Basis, Uebersicht, Buchungsliste

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

finance/tests/test_gui.py

@@ -0,0 +1,13 @@
+def test_pages_require_login(client):
+    for path in ("/", "/buchungen", "/import", "/planung"):
+        r = client.get(path, follow_redirects=False)
+        assert r.status_code in (302, 303), path
+        assert r.headers["location"] == "/login"
+
+
+def test_pages_render_after_login(client):
+    client.post("/login", data={"username": "admin", "password": "geheim"})
+    for path in ("/", "/buchungen"):
+        r = client.get(path)
+        assert r.status_code == 200
+        assert "Finanzberatung" in r.text