fix(ci): bind server to 0.0.0.0 in Docker and use Python healthcheck

Server must bind to 0.0.0.0 inside Docker for client container to reach
it over the Docker network. Also replaced curl healthcheck with Python
urllib since the image doesn't have curl installed.

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

Author: HanSur94

docker-compose.test.yml

@@ -14,23 +14,32 @@ services:
     environment:
       - MATLAB_MCP_AUTH_TOKEN=test-token-for-ci
       - MATLAB_MCP_POOL_MIN_ENGINES=0
+      - MATLAB_MCP_SERVER_HOST=0.0.0.0
     networks:
       - mcp-test-net
     healthcheck:
       test:
         - "CMD"
-        - "sh"
+        - "python"
         - "-c"
         - |
-          curl -sf -X POST http://localhost:8765/mcp \
-            -H "Content-Type: application/json" \
-            -H "Authorization: Bearer test-token-for-ci" \
-            -d '{"jsonrpc":"2.0","method":"initialize","id":0,"params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"healthcheck","version":"0.1"}}}' \
-            --max-time 3 | grep -q '"result"'
-      interval: 2s
-      timeout: 3s
-      retries: 10
-      start_period: 5s
+          import urllib.request, json, sys
+          req = urllib.request.Request(
+              "http://localhost:8765/mcp",
+              data=json.dumps({"jsonrpc":"2.0","method":"initialize","id":0,
+                  "params":{"protocolVersion":"2024-11-05","capabilities":{},
+                  "clientInfo":{"name":"hc","version":"0.1"}}}).encode(),
+              headers={"Content-Type":"application/json",
+                  "Authorization":"Bearer test-token-for-ci"})
+          try:
+              r = urllib.request.urlopen(req, timeout=3)
+              sys.exit(0 if r.status < 500 else 1)
+          except Exception:
+              sys.exit(1)
+      interval: 3s
+      timeout: 5s
+      retries: 15
+      start_period: 10s
 
   client:
     build: .