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/uploader.go

@@ -0,0 +1,80 @@
+package event
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+
+	"tianyan-edge/internal/config"
+)
+
+const maxBuffer = 500
+
+type Uploader struct {
+	cfg    *config.Config
+	events <-chan SuspectedEvent
+	buf    []SuspectedEvent
+}
+
+func NewUploader(cfg *config.Config, events <-chan SuspectedEvent) *Uploader {
+	return &Uploader{cfg: cfg, events: events}
+}
+
+func (u *Uploader) Run(ctx context.Context) {
+	client := &http.Client{Timeout: 10 * time.Second}
+	ticker := time.NewTicker(5 * time.Second)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case ev := <-u.events:
+			if !u.upload(client, ev) {
+				u.buffer(ev)
+			}
+		case <-ticker.C:
+			u.flushBuffer(client)
+		}
+	}
+}
+
+func (u *Uploader) buffer(ev SuspectedEvent) {
+	if len(u.buf) < maxBuffer {
+		u.buf = append(u.buf, ev)
+	} else {
+		log.Println("uploader: offline buffer full, dropping event")
+	}
+}
+
+func (u *Uploader) flushBuffer(client *http.Client) {
+	remaining := u.buf[:0]
+	for _, ev := range u.buf {
+		if !u.upload(client, ev) {
+			remaining = append(remaining, ev)
+		}
+	}
+	u.buf = remaining
+}
+
+func (u *Uploader) upload(client *http.Client, ev SuspectedEvent) bool {
+	url := fmt.Sprintf("%s/api/v1/edge/events/suspected", u.cfg.CloudURL)
+	body, _ := json.Marshal(ev)
+	req, _ := http.NewRequest(http.MethodPost, url, bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", "Bearer "+u.cfg.EdgeToken)
+	resp, err := client.Do(req)
+	if err != nil {
+		log.Printf("uploader: upload error: %v", err)
+		return false
+	}
+	defer resp.Body.Close()
+	ok := resp.StatusCode == 200 || resp.StatusCode == 201
+	if !ok {
+		log.Printf("uploader: upload failed status=%d", resp.StatusCode)
+	}
+	return ok
+}