feat: introduce MCP server, cross-platform runtime, and Showcase UI reorganization

- Showcase UI Reorganization:
  * Move web UI dashboard from root directory into apps/showcase_ui/ for cleaner project structure
  * Add 'artemis ui' CLI command (artemis/interfaces/cli/commands/ui.py) and launcher scripts for the interactive showcase console
- Standalone MCP Server & Notifiers (mcp_server/):
  * Implement dedicated MCP server package with mobile automation tools (device_state, inspect_trace, task_manager, task_runner)
  * Add multi-channel notifiers (AgentAPI, Desktop notifications, Webhooks, File output, and Composite routing)
  * Introduce background task runner and trace store for autonomous mobile execution monitoring
- Cross-Platform Runtime & Toolchain Support:
  * Add artemis/platform/ with OS-specific implementations for Linux, macOS (Darwin), and Windows
  * Add artemis/runtime/supervisor.py for resilient process and agent runtime supervision
  * Add artemis/toolchain/ with dependency resolution and SDK descriptors
  * Add cross-platform launcher scripts (start.sh, start.bat) and installer scripts (scripts/install_deps.*)
- Core Enhancements & Diagnostics:
  * Enhance coordinate normalization, OCR API fallback, and perception pipeline
  * Add credential validation (credentials_validator.py) and system diagnostics
  * Update bilingual documentation (README.md, README_CN.md) and architecture diagrams
- Test Suite Expansion:
  * Add integration tests for cloud gateway, remote ADB, and Artemis login
  * Add unit tests covering core diagnostics, platform detection, toolchain, credentials validator, optional OCR, and MCP tools

artemis/mcp/__init__.py

@@ -0,0 +1,20 @@
+# 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.
+
+"""Internal MCP servers for ARTEMIS engine (ADB server, XML Fuzzy Search)."""
+
+from artemis.mcp.adb_server import mcp as adb_mcp
+from artemis.mcp.xml_search_server import mcp as xml_mcp
+
+__all__ = ["adb_mcp", "xml_mcp"]

artemis/mcp/adb_server.py

@@ -29,9 +29,17 @@ if _REPO_ROOT not in sys.path:
 from adbutils import AdbClient
 from mcp.server.fastmcp import Context, FastMCP
 
+try:
+    from mcp.server.fastmcp.server import Settings as FastMCPSettings
+
+    FastMCPSettings.model_rebuild()
+except Exception:
+    pass
+
 from artemis.clients.ui_automator_client import UIAutomatorClient
 from artemis.context import ArtemisContext, DeviceContext, DevicePlatform
 from artemis.controllers.unified_controller import UnifiedMobileController
+from artemis.platform import platform
 from artemis.utils.app_launch_utils import launch_app_with_retries
 
 # Redirect stdio to prevent logs from breaking MCP JSON-RPC protocol and causing deadlocks.
@@ -130,7 +138,7 @@ def _get_controller():
     ctx = ArtemisContext(
         trace_id="mcp-session",
         device=DeviceContext(
-            host_platform="LINUX",
+            host_platform=platform.os_type.name,
             mobile_platform=DevicePlatform.ANDROID,
             device_id=device_id,
             device_width=width,

artemis/mcp/xml_search_server.py

@@ -25,6 +25,13 @@ if _REPO_ROOT not in sys.path:
 # pylint: disable=wrong-import-position
 from mcp.server.fastmcp import FastMCP
 
+try:
+    from mcp.server.fastmcp.server import Settings as FastMCPSettings
+
+    FastMCPSettings.model_rebuild()
+except Exception:
+    pass
+
 from artemis.data_engine.storage import StorageManager
 
 mcp = FastMCP("Android_XML_Fuzzy_Search")
@@ -83,7 +90,7 @@ def serialize_node(node, max_depth=1):
 
 @mcp.tool()
 def search_ui(image_hash: str, query: str, threshold: float = 0.6) -> dict:
-    """Search for text in UI data (XML and OCR) retrieved from Data Engine by image hash.
+    """Search for text in UI data retrieved from Data Engine by image hash.
 
     Args:
         image_hash: The SHA-256 hash of the image.
@@ -153,7 +160,7 @@ def parse_bounds(bounds_str):
 
 @mcp.tool()
 def search_by_coordinates(image_hash: str, x: int, y: int) -> str:
-    """Search for elements in UI data (XML and OCR) retrieved from Data Engine by image hash that overlap with the given coordinates.
+    """Search for elements in UI data retrieved from Data Engine by image hash that overlap with the given coordinates.
 
     Args:
         image_hash: The SHA-256 hash of the image.
@@ -161,7 +168,7 @@ def search_by_coordinates(image_hash: str, x: int, y: int) -> str:
         y: The Y coordinate.
 
     Returns:
-        A string containing the matching nodes and OCR results.
+        A string containing the matching nodes.
     """
     db_path = os.getenv("DATA_ENGINE_DB_PATH")
     if not db_path: