Stats: range buttons follow the retention settings

The Statistics page offers only the ranges kept (longest of the minute,
hour and day retentions), adds 1y and 2y when the daily data covers them,
caps the heatmap at the hourly retention and links to Explore within
retention.queries. Status and explore send retention_seconds. The query
log error names stats.retention.queries.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -42,6 +42,14 @@ All notable changes to Jarl are documented here. The format follows
 
 ### Changed
 
+- The Statistics page's range buttons follow `stats.retention`: ranges
+  longer than any data kept are left out, and **1y** and **2y** appear
+  when `retention.day` (or `retention.hour`) covers them (with the
+  default 730d, both do). The busiest-times heatmap says how far back it
+  really goes (at most `retention.hour`), and links to the Explore page
+  keep within `retention.queries` instead of assuming 7 days.
+  `GET /stats/status` and `GET /stats/explore` add `retention_seconds`.
+
 - A reverse zone's missing PTR records count only its own view's A and
   AAAA records. An address only another view's records use (an internal
   host, seen from the vps view's copy of `10.0.10.in-addr.arpa`) is no
@@ -97,6 +105,8 @@ All notable changes to Jarl are documented here. The format follows
 
 ### Fixed
 
+- The "query log is off" error named a setting that doesn't exist,
+  `stats.query_retention`; it's `stats.retention.queries`.
 - `jarl zone show` for a reverse zone printed only "and 1 more" under
   "Other views:" when the server was older than the CLI (0.6.1-rc.2
   sends the count but not the addresses). It now prints just the count