test: add tests for Application class

Need more attention here. Very difficult to test the keyboard interaction with questionary. Going to try using pexpect soon to hopefully add better coverage.

tests/application_test.py

@@ -0,0 +1,18 @@
+# type: ignore
+"""Tests for the application module."""
+
+
+from obsidian_metadata._config import Config
+from obsidian_metadata.models.application import Application
+
+
+def test_load_vault(test_vault) -> None:
+    """Test application."""
+    vault_path = test_vault
+    config = Config(config_path="tests/fixtures/test_vault_config.toml", vault_path=vault_path)
+    app = Application(config=config, dry_run=False)
+    app.load_vault()
+
+    assert app.dry_run is False
+    assert app.config == config
+    assert app.vault.num_notes() == 2