test: add comprehensive unit, integration, and e2e test suites

Introduce complete test coverage for the ARTEMIS platform across multiple layers:
Unit tests: Add tests for agent nodes (Planner, Operator, Validator, Diagnoser, FlashRunner, Explorer), tools, utils (OCR/XML fusion, UI hierarchy), and data engine.
Integration tests: Add live tool verification, reactive runner, IME, and standalone workflow tests.
E2E tests: Add end-to-end scenario tests for media playback and failure recovery flows.
Fixtures & mocks: Add mock inputs (audio, video, screenshot) and test utilities.

tests/unit/test_cli.py

@@ -0,0 +1,65 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Unit tests for ARTEMIS Unified CLI application."""
+
+from typer.testing import CliRunner
+from artemis.interfaces.cli.main import app
+
+runner = CliRunner()
+
+
+def test_cli_help():
+    """Verify top-level CLI help returns status 0 and lists core subcommands."""
+    result = runner.invoke(app, ["--help"])
+    assert result.exit_code == 0
+    assert "Artemis: Autonomous Multimodal Android Agent" in result.output
+    assert "run" in result.output
+    assert "batch" in result.output
+    assert "bench" in result.output
+    assert "server" in result.output
+    assert "trace" in result.output
+    assert "mcp" in result.output
+
+
+def test_cli_version():
+    """Verify --version returns version banner."""
+    result = runner.invoke(app, ["--version"])
+    assert result.exit_code == 0
+    assert "Artemis Agent Platform" in result.output
+
+
+def test_cli_run_help():
+    """Verify 'artemis run --help' displays execution options."""
+    result = runner.invoke(app, ["run", "--help"])
+    assert result.exit_code == 0
+    assert "--profile" in result.output
+    assert "--locked-app" in result.output
+    assert "--traces-path" in result.output
+
+
+def test_cli_batch_help():
+    """Verify 'artemis batch --help' displays batch options."""
+    result = runner.invoke(app, ["batch", "--help"])
+    assert result.exit_code == 0
+    assert "--file" in result.output
+    assert "--delay" in result.output
+
+
+def test_cli_trace_help():
+    """Verify 'artemis trace --help' lists trace subcommands."""
+    result = runner.invoke(app, ["trace", "--help"])
+    assert result.exit_code == 0
+    assert "list" in result.output
+    assert "view" in result.output