Fix infinite loop in wait_for_port.sh and keycloak healthcheck race

1. wait_for_port.sh used [[ ]] (bash) but Makefile calls it via 'sh'
   (dash on Ubuntu). The counter never triggered exit, looping forever
   for 6h until GH Actions timeout. Fixed: use POSIX [ ] syntax.

2. Keycloak healthcheck tested management port 9990 (up in ~10s) but
   the HTTP server on 8080 takes ~29s. Registry started before 8080
   was ready, failed to fetch OIDC config, crashed. Fixed: test 8080.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: sntiwari1

build/wait_for_port.sh

@@ -5,7 +5,7 @@ i=0
 while ! curl localhost:$1; do
   sleep 10
   ((i=i+1))
-  if [[ $i -gt 60 ]]; then
+  if [ "$i" -gt 60 ]; then
     echo "Failed to get the service in sane state!"
     exit 1;
   fi

docker-compose-v1.yml

@@ -145,7 +145,7 @@ services:
       - KEYCLOAK_IMPORT=/opt/jboss/keycloak/imports/realm-export.json
       - PROXY_ADDRESS_FORWARDING=true
     healthcheck:
-      test: ['CMD-SHELL', 'curl -f http://localhost:9990/ || exit 1']
+      test: ['CMD-SHELL', 'curl -f http://localhost:8080/auth/ || exit 1']
       interval: 30s
       timeout: 10s
       retries: 10