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/tools/test_log_tool.py

@@ -0,0 +1,115 @@
+# 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.
+
+from unittest.mock import AsyncMock, MagicMock, patch
+
+from artemis.context import ArtemisContext
+from artemis.graph.state import State
+from artemis.tools.base import ArtemisTool, ToolRegistry
+from artemis.tools.log_tool import (
+    AnalyzeLogs,
+    AnalyzeLogsArgs,
+    AnalyzeLogsTool,
+    LogTool,
+    analyze_logs,
+    analyze_logs_wrapper,
+    get_analyze_logs_tool,
+)
+import pytest
+
+
+@pytest.mark.asyncio
+async def test_analyze_logs_tool_execution():
+    mock_ctx = MagicMock(spec=ArtemisContext)
+    mock_ctx.data_engine = None
+
+    mock_state = MagicMock(spec=State)
+
+    expected_output = "Found 2 errors in system log: NullPointerException at line 42."
+
+    mock_analyst = MagicMock()
+    mock_analyst.run = AsyncMock(return_value=expected_output)
+
+    with patch(
+        "artemis.tools.log_tool.LogAnalyzerNode",
+        return_value=mock_analyst,
+    ):
+        tool = get_analyze_logs_tool(mock_ctx)
+
+        result = await tool.ainvoke(
+            {
+                "specific_query": "Check for crash exceptions",
+                "state": mock_state,
+            }
+        )
+
+        mock_analyst.run.assert_called_once_with("Check for crash exceptions", mock_state)
+        assert result == expected_output
+
+
+@pytest.mark.asyncio
+async def test_analyze_logs_tool_direct_call():
+    mock_ctx = MagicMock(spec=ArtemisContext)
+    mock_state = MagicMock(spec=State)
+
+    mock_analyst = MagicMock()
+    mock_analyst.run = AsyncMock(return_value="Log scan complete.")
+
+    with patch(
+        "artemis.tools.log_tool.LogAnalyzerNode",
+        return_value=mock_analyst,
+    ):
+        result = await analyze_logs(
+            ctx=mock_ctx,
+            specific_query="Find ANR",
+            state=mock_state,
+        )
+        mock_analyst.run.assert_called_once_with("Find ANR", mock_state)
+        assert result == "Log scan complete."
+
+
+@pytest.mark.asyncio
+async def test_analyze_logs_tool_no_context():
+    result = await analyze_logs(
+        ctx=None,
+        specific_query="Find crash",
+    )
+    assert result == "Error: ArtemisContext is required for LogAnalyzer."
+
+
+def test_analyze_logs_tool_subclass_and_registry():
+    """Verify AnalyzeLogsTool is an ArtemisTool subclass and registered in ToolRegistry."""
+    assert issubclass(AnalyzeLogsTool, ArtemisTool)
+    assert issubclass(AnalyzeLogs, ArtemisTool)
+    assert issubclass(LogTool, ArtemisTool)
+    assert isinstance(analyze_logs, ArtemisTool)
+    assert isinstance(analyze_logs, AnalyzeLogsTool)
+
+    assert analyze_logs.name == "analyze_logs"
+    assert analyze_logs.category == "custom"
+    assert analyze_logs.args_schema == AnalyzeLogsArgs
+
+    # Registry lookup
+    reg_tool = ToolRegistry.get("analyze_logs")
+    assert reg_tool is not None
+    assert isinstance(reg_tool, AnalyzeLogsTool)
+
+    # GenAI FunctionDeclaration export
+    declaration = analyze_logs.to_genai_declaration()
+    assert declaration.name == "analyze_logs"
+    assert "specific_query" in declaration.parameters.properties
+
+    # Wrapper check
+    assert analyze_logs_wrapper is not None
+    assert analyze_logs_wrapper.tool_fn_getter == get_analyze_logs_tool