Add example env and healthcheck

example.env

@@ -0,0 +1,19 @@
+# Required
+MAXMIND_LICENSE_KEY=
+
+# Optional (helps with rate limits)
+PDB_API_KEY=
+
+# Output data location shared with the detection service
+OUT_DIR=/data
+
+# PeeringDB settings
+PDB_BASE=https://www.peeringdb.com
+PDB_INFO_TYPE=Educational/Research
+PDB_LIMIT=250
+
+# HTTP settings
+HTTP_TIMEOUT=30
+
+# Update interval (seconds, default 30 days)
+INTERVAL_SECONDS=2592000