fix: add ClickHouse password authentication

ClickHouse default user had no password, causing auth failures on recent
CH versions. Set password via from_env in clickhouse-users.xml, pass
credentials in JDBC URLs to SaaS services and tenant server containers.

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

docker-compose.yml

@@ -196,12 +196,14 @@ services:
   clickhouse:
     image: clickhouse/clickhouse-server:latest
     restart: unless-stopped
+    environment:
+      CLICKHOUSE_PASSWORD: ${CLICKHOUSE_PASSWORD:-cameleer_ch}
     volumes:
       - chdata:/var/lib/clickhouse
       - ./docker/clickhouse-init.sql:/docker-entrypoint-initdb.d/init.sql:ro
       - ./docker/clickhouse-users.xml:/etc/clickhouse-server/users.d/default-user.xml:ro
     healthcheck:
-      test: ["CMD-SHELL", "clickhouse-client --query 'SELECT 1'"]
+      test: ["CMD-SHELL", "clickhouse-client --password ${CLICKHOUSE_PASSWORD:-cameleer_ch} --query 'SELECT 1'"]
       interval: 10s
       timeout: 5s
       retries: 3