added nexus package manager

docker-compose/nexus/.env.example

@@ -0,0 +1,21 @@
+# service image tag (latest stable as of Aug 2026)
+nexus_image_tag=3.90.5
+
+# domain variables - internal, self-signed *.home.server (no public DNS, no ACME)
+nexus_main_domain=nexus.home.server
+nexus_docker_domain=docker.home.server
+
+# restart policy
+restart_policy=always
+
+# nexus admin password (first-login password; change it after setup)
+nexus_admin_pass=CHANGE_ME
+
+# --- Resource tuning for an 8GB / DDR3 / 4-core host ---
+nexus_heap=1536m
+nexus_direct_mem=512m
+nexus_mem_limit=2560m
+nexus_mem_reservation=1536m
+
+# Docker registry group repo's internal HTTP connector port (created in Nexus UI, see SETUP.md)
+nexus_docker_connector_port=5005