fix(conversation-assistant): fix service registry discovery in install.sh

- Change from GET with query params to POST with JSON body
- Fix response parsing: 'instances' → 'services' to match API
- Prefer host (domain) over ipAddress for proper SSL/routing
- Auto-detect https scheme for domain names

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

features/conversation-assistant/macos/install.sh

@@ -158,22 +158,30 @@ discover_service_url() {
     # Try to discover conversation-assistant service from service-registry
     local registry_url="${SERVICE_REGISTRY_URL:-http://localhost:30000}"
 
-    # Try to discover the service
+    # Try to discover the service (POST with JSON body)
     local discovery_response
-    discovery_response=$(curl -s --connect-timeout 2 "$registry_url/registry/discover?serviceName=conversation-assistant&healthy=true" 2>/dev/null || echo "")
+    discovery_response=$(curl -s --connect-timeout 2 \
+        -X POST \
+        -H "Content-Type: application/json" \
+        -d '{"serviceName":"conversation-assistant","healthy":true}' \
+        "$registry_url/registry/discover" 2>/dev/null || echo "")
 
     if [[ -n "$discovery_response" && "$discovery_response" != *"error"* ]]; then
-        # Parse the first instance's URL from JSON response
+        # Parse the first service's URL from JSON response
         local service_url
         service_url=$(echo "$discovery_response" | python3 -c "
 import sys, json
 try:
     data = json.load(sys.stdin)
-    if data.get('instances') and len(data['instances']) > 0:
-        inst = data['instances'][0]
-        ip = inst.get('ipAddress', 'localhost')
-        port = inst.get('port', 3105)
-        print(f'http://{ip}:{port}')
+    services = data.get('services', [])
+    if services and len(services) > 0:
+        svc = services[0]
+        # Prefer host (domain) over ipAddress for proper SSL/routing
+        host = svc.get('host') or svc.get('ipAddress', 'localhost')
+        port = svc.get('port', 3105)
+        # Use https if host is a domain name
+        scheme = 'https' if '.' in host and not host.replace('.','').isdigit() else 'http'
+        print(f'{scheme}://{host}:{port}')
 except:
     pass
 " 2>/dev/null)