feat: improve session navigation

tests/unit/test_cli.py

@@ -1,3 +1,4 @@
+import sqlite3
 import tempfile
 import unittest
 from pathlib import Path
@@ -167,6 +168,76 @@ class CliTests(unittest.TestCase):
         )
         self.assertIn("Gemini-Schlüssel vorhanden: ja", output)
 
+    def test_numbered_sessions_load_rename_and_search(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            store = SQLiteSessionStore(Path(directory) / "sessions.sqlite3")
+            service = ChatService(store, _FakeProvider())
+            first = service.new_session()
+            service.send(first.id, "Erste Frage")
+            second = service.new_session()
+            service.send(second.id, "Zweite Frage")
+            shown_before = service.list_sessions()
+            target = shown_before[1]
+            inputs = iter(
+                [
+                    "/sessions",
+                    "/load 2",
+                    "/rename Gefundene Sitzung",
+                    "/search Gefundene",
+                    "/exit",
+                ]
+            )
+            output: list[str] = []
+
+            result = run_chat(
+                service,
+                session_id=first.id,
+                input_fn=lambda _prompt: next(inputs),
+                output=output.append,
+            )
+            renamed_title = store.get_session(target.id).title
+
+        self.assertEqual(result, 0)
+        self.assertTrue(any(line.startswith("1. ") and "Frage" in line for line in output))
+        self.assertIn(f"Sitzung geladen: {target.id}", output)
+        self.assertEqual(renamed_title, "Gefundene Sitzung")
+        self.assertTrue(any("Gefundene Sitzung" in line for line in output))
+
+    def test_load_accepts_unique_prefix_and_rejects_ambiguous_prefix(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            database = Path(directory) / "sessions.sqlite3"
+            store = SQLiteSessionStore(database)
+            service = ChatService(store, _FakeProvider())
+            active = service.new_session()
+            with sqlite3.connect(database) as connection:
+                connection.executemany(
+                    """
+                    INSERT INTO sessions
+                        (id, created_at, updated_at, provider, model, title, last_provider)
+                    VALUES (?, '2026-01-01', '2026-01-01',
+                            'ollama', 'test-model', ?, 'ollama')
+                    """,
+                    (
+                        ("shared-111", "Eins"),
+                        ("shared-222", "Zwei"),
+                        ("unique-333", "Drei"),
+                    ),
+                )
+            connection.close()
+            inputs = iter(["/load unique", "/load shared", "/exit"])
+            output: list[str] = []
+
+            result = run_chat(
+                service,
+                session_id=active.id,
+                input_fn=lambda _prompt: next(inputs),
+                output=output.append,
+            )
+
+        self.assertEqual(result, 0)
+        self.assertIn("Sitzung geladen: unique-333", output)
+        self.assertTrue(any("nicht eindeutig" in line for line in output))
+
     def test_gemini_configuration_defaults_to_no(self) -> None:
         with tempfile.TemporaryDirectory() as directory:
             path = Path(directory) / "javis.toml"