added postgres & made structure changes

homelab/applications/postgres/start.sh

@@ -0,0 +1,13 @@
+#!/bin/zsh
+# Exit immediately if a command exits with a non-zero status.
+set -e
+
+echo "--- Starting Docker Secret Management ---"
+# Mount secrets
+export POSTGRES_USER="$(op read 'op://NAxS Homelab/Postgres Homelab/username')"
+export POSTGRES_PASSWORD="$(op read 'op://NAxS Homelab/Postgres Homelab/password')"
+
+# Bring up container
+docker compose up -d
+
+echo "--- Docker Secret Management Complete ---"