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>

docs/api.md

@@ -579,12 +579,12 @@ Needs `stats:read`. When statistics are disabled, every endpoint but
 
 | Method | Path | Query | Returns |
 |--------|------|-------|---------|
-| GET | `/stats/status` | | `{enabled, query_log, statistics_channel, log_file, last_poll, last_log_line, log_lines_read, first_data, retention, warnings}` |
+| GET | `/stats/status` | | `{enabled, query_log, statistics_channel, log_file, last_poll, last_log_line, log_lines_read, first_data, retention, retention_seconds, warnings}`: `retention` has `minute`, `hour`, `day`, `queries` as `"7d"`, `retention_seconds` the same in seconds (`queries` 0 without a query log) |
 | GET | `/stats/summary` | `since` (90m, 24h, 7d, 2w; default 24h), `top` (default 10) | totals, `avg_qps`, `peak`, `rcodes`, `qtypes`, `views`, `zones`, `answers`, `transport`, `cache_hit_ratio`, `nxdomain_ratio` (without blocked answers), `blocked`, `blocked_ratio`, `blocklists` (blocked per list; `rules` for your rules), `tops` |
 | GET | `/stats/timeline` | `since`, `step` (auto, 1m, 5m, 15m, 1h, 6h, 1d), `key` (repeatable or comma separated; `rcode:*` = every counter of a group; default `queries`) | `{step, times: [unix...], series: [{key, values}]}` |
 | GET | `/stats/top` | `kind` (name, client, nxdomain, servfail, refused, blocked, blocked_client), `since`, `limit` (default 20) | `[{key, count}]`; client, refused and blocked_client entries add `name`, the host name of Jarl's record for the address (the summary's client list too) |
 | GET | `/stats/heatmap` | `since` (default 28d), `key` (default queries) | `{key, from, avg[7][24], samples[7][24]}`, Monday first, local time, `-1` = no data |
-| GET | `/stats/explore` | `?client=&name=&domain=&view=&type=&rcode=&blocked=yes\|no\|LIST&since=24h&views=`; each takes several values, comma separated (any of them), `!value` to leave one out, and names `*.example.com` for it and below | The query log for a filter ([stats.md](stats.md#exploring)): `total`, `blocked`, `series` (per `step` seconds: `t`, `count`, `blocked`), `by` (top 15 of each dimension the filter leaves open: client, name, view, type, rcode, blocked; clients with `name`), `recent` (latest 100: ts, client, client_name, view, name, type, rcode, blocked), `oldest`, `retention`, `client_name`. 404 `query_log_off` without a query log |
+| GET | `/stats/explore` | `?client=&name=&domain=&view=&type=&rcode=&blocked=yes\|no\|LIST&since=24h&views=`; each takes several values, comma separated (any of them), `!value` to leave one out, and names `*.example.com` for it and below | The query log for a filter ([stats.md](stats.md#exploring)): `total`, `blocked`, `series` (per `step` seconds: `t`, `count`, `blocked`), `by` (top 15 of each dimension the filter leaves open: client, name, view, type, rcode, blocked; clients with `name`), `recent` (latest 100: ts, client, client_name, view, name, type, rcode, blocked), `oldest`, `retention` (`"7d"`) and `retention_seconds`, `client_name`. 404 `query_log_off` without a query log |
 | GET | `/stats/server` | | `{server: {rss, mem_in_use, cpu_percent, threads, pid, cache_rrsets, cache_mem, sockets_udp, sockets_tcp, recursion_highwater, tcp_highwater, version, boot_time, config_time, host: {mem_total, mem_available, load, cpus, uptime}}, named: {recursive_clients, tcp_clients, zones, cpus, worker_threads}, disks: [{path, holds, total, free}], database: {path, bytes, query_log_rows}}`; gauges over time: `/stats/timeline?key=g:named:rss` (averages, -1 without a sample) |
 | GET | `/stats/breakdown` | `group` (qtype, rcode, view, zone, answer, transport, rtt, dnssec, cache, ratelimit, blocklist), `since` | `[{key, count}]` |
 

docs/stats.md

@@ -263,7 +263,11 @@ database, roughly in proportion to the number of views.
   lists for `retention.hour`, daily ones for `retention.day`. Older data is
   deleted every hour.
 - Charts use the finest resolution that covers the range: minutes up to 48
-  hours, hours up to 90 days, days beyond.
+  hours (and `retention.minute`), hours up to `retention.hour`, days beyond.
+- The Statistics page offers only the ranges the data is kept for: up to 90
+  days with the defaults, plus a year and 2 years when `retention.day` (or
+  `retention.hour`) is that long. The Explore page offers the ranges up to
+  `retention.queries`.
 - Top lists are exact within an hour (up to 200,000 distinct names or
   clients per hour, beyond which the rarest are dropped). Daily lists are
   built from the hourly top lists, so for very long tails they are