init: tianyan-edge edge agent with Ascend NPU inference backend

- Go main process: stream ingestor, infer client, event uploader,
  heartbeat, config agent, OTA agent
- Python inference server rewritten to use CANN ACL (acl module)
  replacing ultralytics/PyTorch; supports YOLOv8 raw and YOLOv10
  NMS-free output formats via OUTPUT_FORMAT env var
- systemd services for edge-agent and edge-infer
- build/install/package scripts targeting arm64

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

internal/event/types.go

@@ -0,0 +1,13 @@
+package event
+
+type SuspectedEvent struct {
+	EventID   string    `json:"event_id"`
+	EdgeID    string    `json:"edge_id"`
+	DeviceID  string    `json:"device_id"`
+	StreamURL string    `json:"stream_url"`
+	TS        float64   `json:"ts"`
+	Class     string    `json:"class"`
+	Conf      float64   `json:"conf"`
+	BBox      []float64 `json:"bbox"`
+	ImageB64  string    `json:"image_b64"`
+}