R7: pin docker_stats api_version to 1.44

The receiver defaults to Docker API 1.25, but the contour daemon's minimum is
1.40 (it speaks up to 1.54), so otelcol crash-looped on start with "client
version 1.25 is too old". Pinning api_version to 1.44 (accepted by both the
receiver's bundled client and the daemon) starts the receiver cleanly —
verified by running the image against the host socket ("Everything is ready",
no start error).

deploy/otelcol/config.yaml

@@ -14,6 +14,10 @@ receivers:
   # gauge where 100 == one core (it mirrors `docker stats` CPU%).
   docker_stats:
     endpoint: unix:///var/run/docker.sock
+    # The receiver defaults to Docker API 1.25, but the daemon's minimum is 1.40
+    # (server speaks up to 1.54); pin a version both the receiver's client and the
+    # daemon accept, else the receiver fails to start ("client version too old").
+    api_version: "1.44"
     collection_interval: 30s
     metrics:
       container.cpu.utilization: