refactor: clean up legacy code, rename hopper to entity_extractor, and add third-party notices

- Add NOTICE file and README license references for mobile-use and finalrun-agent
- Add derivative attribution headers to 17 files derived from mobile-use
- Rename hopper agent to entity_extractor across prompts, tools, and configs
- Remove obsolete adb_tunnel, ApiBaseUrl, and legacy CLI utility scripts
- Replace legacy examples with native Artemis diagnostic and workflow examples
- Update unit and tool tests to validate entity_extractor and SDK builders

tests/unit/agents/test_entity_extractor.py

@@ -0,0 +1,76 @@
+# 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 entity extraction and package resolver."""
+
+from unittest.mock import AsyncMock, MagicMock, patch
+import pytest
+
+from artemis.agents.entity_extractor.entity_extractor import (
+    ExtractionResult,
+    extract_entity,
+)
+
+
+def test_extraction_result_model():
+    """Verify ExtractionResult attributes and validation."""
+    res = ExtractionResult(found=True, output="com.google.android.apps.nexuslauncher", reason="Exact match")
+    assert res.found is True
+    assert res.output == "com.google.android.apps.nexuslauncher"
+    assert res.reason == "Exact match"
+
+
+@pytest.mark.asyncio
+async def test_extract_entity_success():
+    """Verify successful LLM entity extraction invocation."""
+    mock_ctx = MagicMock()
+    mock_llm = MagicMock()
+    expected_result = ExtractionResult(
+        found=True,
+        output="com.google.android.calculator",
+        reason="Found calculator package in list",
+    )
+    mock_llm.ainvoke = AsyncMock(return_value=expected_result)
+
+    with patch("artemis.agents.entity_extractor.entity_extractor.get_llm") as mock_get_llm:
+        mock_get_llm.return_value.with_structured_output.return_value = mock_llm
+        result = await extract_entity(
+            request="Calculator",
+            data="com.google.android.calculator\ncom.google.android.calendar",
+            ctx=mock_ctx,
+        )
+
+    assert result.found is True
+    assert result.output == "com.google.android.calculator"
+    assert result.reason == "Found calculator package in list"
+
+
+@pytest.mark.asyncio
+async def test_extract_entity_handles_exception():
+    """Verify extraction returns a graceful failure result when LLM throws an exception."""
+    mock_ctx = MagicMock()
+    mock_llm = MagicMock()
+    mock_llm.ainvoke = AsyncMock(side_effect=RuntimeError("LLM connection timed out"))
+
+    with patch("artemis.agents.entity_extractor.entity_extractor.get_llm") as mock_get_llm:
+        mock_get_llm.return_value.with_structured_output.return_value = mock_llm
+        result = await extract_entity(
+            request="Settings",
+            data="com.android.settings",
+            ctx=mock_ctx,
+        )
+
+    assert result.found is False
+    assert result.output is None
+    assert "LLM extraction error" in result.reason