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

mcp_server/utils/trace_store.py

@@ -0,0 +1,108 @@
+# 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.
+
+"""Trace storage and lifecycle management for MCP background automation tasks."""
+
+import json
+import os
+import time
+from typing import Any
+
+try:
+    from artemis.config.paths import get_traces_dir
+
+    TRACES_DIR = str(get_traces_dir())
+except Exception:
+    PROJECT_ROOT = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+    TRACES_DIR = os.path.join(PROJECT_ROOT, "traces")
+
+
+def get_trace_dir(trace_id: str) -> str:
+    """Returns the absolute path to the directory for a given trace_id."""
+    return os.path.join(TRACES_DIR, trace_id)
+
+
+def get_status_path(trace_id: str) -> str:
+    """Returns the absolute path to the status.json file for a given trace_id."""
+    return os.path.join(get_trace_dir(trace_id), "status.json")
+
+
+def init_trace(
+    trace_id: str,
+    task_desc: str,
+    model: str,
+    conversation_id: str,
+) -> dict[str, Any]:
+    """Initializes the trace directory and creates the initial status.json file."""
+    trace_dir = get_trace_dir(trace_id)
+    os.makedirs(trace_dir, exist_ok=True)
+
+    status_data: dict[str, Any] = {
+        "trace_id": trace_id,
+        "task_desc": task_desc,
+        "model": model,
+        "conversation_id": conversation_id,
+        "status": "running",
+        "start_time": time.time(),
+        "end_time": None,
+        "error": None,
+        "result": None,
+    }
+
+    write_status(trace_id, status_data)
+    return status_data
+
+
+def read_status(trace_id: str) -> dict[str, Any] | None:
+    """Reads and returns the status.json for a given trace_id, or None if it doesn't exist."""
+    path = get_status_path(trace_id)
+    if not os.path.exists(path):
+        return None
+    try:
+        with open(path, encoding="utf-8") as f:
+            return json.load(f)
+    except Exception:
+        return None
+
+
+def write_status(trace_id: str, data: dict[str, Any]) -> None:
+    """Writes the given status dictionary to the trace's status.json."""
+    path = get_status_path(trace_id)
+    os.makedirs(os.path.dirname(path), exist_ok=True)
+    with open(path, "w", encoding="utf-8") as f:
+        json.dump(data, f, indent=2, ensure_ascii=False)
+
+
+def update_trace_status(
+    trace_id: str,
+    status: str,
+    error: str | None = None,
+    result: Any | None = None,
+) -> dict[str, Any] | None:
+    """Updates specific fields of the status.json for a given trace_id."""
+    data = read_status(trace_id)
+    if not data:
+        return None
+
+    data["status"] = status
+    if status in ("completed", "failed", "cancelled"):
+        data["end_time"] = time.time()
+
+    if error is not None:
+        data["error"] = error
+    if result is not None:
+        data["result"] = result
+
+    write_status(trace_id, data)
+    return data