Initial commit - Phase 3/4

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/backend/ble/__init__.py

@@ -0,0 +1,48 @@
+"""BLE GATT server implementation for Dangerous Pi.
+
+This module provides Bluetooth Low Energy (BLE) GATT server functionality
+that reuses the service layer for business logic, ensuring consistency
+with the REST API.
+
+Components:
+- DangerousPiGATTServer: GATT handlers that call service layer
+- BlueZGATTAdapter: Bridges bless library to GATT handlers
+- Characteristic UUIDs: Service and characteristic definitions
+"""
+
+from .gatt_server import DangerousPiGATTServer
+from .characteristics import (
+    PM3CharacteristicUUIDs,
+    WiFiCharacteristicUUIDs,
+    SystemCharacteristicUUIDs,
+    UpdateCharacteristicUUIDs,
+)
+
+# BlueZ adapter (requires bless library)
+try:
+    from .bluez_adapter import (
+        BlueZGATTAdapter,
+        get_ble_adapter,
+        start_ble_server,
+        stop_ble_server,
+    )
+    BLESS_AVAILABLE = True
+except ImportError:
+    BlueZGATTAdapter = None
+    get_ble_adapter = None
+    start_ble_server = None
+    stop_ble_server = None
+    BLESS_AVAILABLE = False
+
+__all__ = [
+    "DangerousPiGATTServer",
+    "PM3CharacteristicUUIDs",
+    "WiFiCharacteristicUUIDs",
+    "SystemCharacteristicUUIDs",
+    "UpdateCharacteristicUUIDs",
+    "BlueZGATTAdapter",
+    "get_ble_adapter",
+    "start_ble_server",
+    "stop_ble_server",
+    "BLESS_AVAILABLE",
+]