chore: optimize Dockerfile apt source compatibility and update edge.yaml cloud/ota URLs to port 9000

- Dockerfile: support both legacy sources.list and DEB822 format for apt mirror
- Dockerfile: use official python:3.9-slim instead of Huawei Cloud SWR mirror
- .dockerignore: exclude !build/edge-agent to avoid build artifact in context
- edge.yaml: change cloud_url from 8004 to 9000 (stream-gateway)
- edge.yaml: change ota_url from 8087 to 9000
- Add Dockerfile.bak and buildkitd.toml

data/config/edge.yaml

@@ -1,6 +1,6 @@
 device_uuid: 8541db9f77826e39605ef2c032f8fb93
 edge_id: edge-demo-001
-cloud_url: http://101.36.73.102:8004
+cloud_url: http://101.36.73.102:9000
 mqtt_broker: tcp://101.36.73.102:1883
 mqtt_user: ""
 mqtt_pass: ""
@@ -12,5 +12,5 @@ infer_fps: 2
 infer_workers: 3
 conf_threshold: 0.2
 dedup_window_sec: 30
-ota_url: http://101.36.73.102:8087
+ota_url: http://101.36.73.102:9000
 version: 1.0.0