DNS blocklists asked in the background, verdicts kept (closes #104)

Work in progress.

Model: opus-5-5

internal/reputation/reputation.go

@@ -2,8 +2,10 @@
 // blocklists of SWWAF_BLOCKLIST_URLS, and the file of AS:percent lines
 // SWWAF_ASN_LIMIT_PERCENT_URL names. It keeps the last good copy of each,
 // whole, comment lines included, which is used while a fetch fails, and
-// when each was last tried, which the state package writes to
-// reputation.json and reads from it, so that a restart keeps them too.
+// when each was last tried. It also asks the DNSBL zones of
+// SWWAF_DNSBL_ZONES about clients, and keeps their verdicts. The state
+// package writes all of these to reputation.json and reads them from it,
+// so that a restart keeps them too.
 package reputation
 
 import (