Rename the settings whose names do not say what they control (closes #234)

Applies the setting renames of the naming audit under the SWW_WAF_ and
SWW_RPROXY_ prefixes, with sneak's names for the IP reputation cache
time and the two time limits, which now take milliseconds. The rproxy
log field default_disposition becomes waf_backend_no_answer, and
config.Config and config.FromEnvironment become config.WAF and
config.WAFFromEnvironment. Go fields, test names and prose follow. No
aliases; nothing reads the old names.

Model: opus-5-5

docs/request-log.md

@@ -128,8 +128,8 @@ Every one of these lines has:
     - `rule_files`: `rule_id` and `rule_action`, of the rule that refused it;
     - `header_limits`: `fields`, `fields_limit`, `cookies` and `cookies_limit`;
     - `core_rule_set`: `score`, and `threshold`,
-      `SWW_WAF_CORE_RULE_SET_ANOMALY_THRESHOLD`;
-    - `refusal_limit`: `window`, `count` and `limit`, of the error burst;
+      `SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD`;
+    - `refusal_limit`: `window`, `count` and `limit`, of the refusal limit;
     - `byte_limits`: `window`, `count` and `limit`, the count in bytes.
 - `after_answer_heuristic`: the heuristic that banned the client after `waf`
   answered the request, in `observe` mode too: `refusal_limit` or `byte_limits`.
@@ -148,7 +148,7 @@ Every one of these lines has:
   holds:
     - `minute`, `hour` and `day`: requests;
     - `minute_bytes`, `hour_bytes` and `day_bytes`: the body bytes
-      `SWW_WAF_BYTES_COUNT` names, in that window.
+      `SWW_WAF_BYTES_COUNTED` names, in that window.
 
     A count can have a fraction (see "Counting method" in
     [`SPEC.md`](../SPEC.md)). The bytes counted for an allowed request and its
@@ -158,7 +158,8 @@ Every one of these lines has:
 - `limit_hit`: the limit broken:
     - `minute`, `hour` or `day` for a rate limit;
     - `minute_bytes`, `hour_bytes` or `day_bytes` for a byte limit;
-    - `minute_refusals` for the error burst (`SWW_WAF_ERROR_BURST_THRESHOLD`).
+    - `minute_refusals` for the refusal limit
+      (`SWW_WAF_REFUSALS_LIMIT_PER_MINUTE`).
 
     When the bytes counted for a request and its response break a limit, the
     request has been passed on whole, so its `action` stays `forward`. Only its
@@ -233,14 +234,15 @@ meanings where they differ:
   was sooner. It includes the wait for `waf`.
 - `duration_response_ms`: milliseconds from then until the end of the answer.
 - `disposition`: what was done with the request: `allow`, `deny` or `close`. It
-  is `waf`'s answer, or the value of `SWW_RPROXY_DEFAULT_DISPOSITION`. It is
-  left out when:
+  is `waf`'s answer, or the value of
+  `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION`. It is left out when:
     - `waf` was not asked, as for the health check;
     - the visitor went away while `waf` was being asked;
     - `waf`'s answer had no valid `X-Sww-Disposition`;
     - `rproxy` could not pass on `waf`'s answer, and answered `502`.
-- `default_disposition`: `true` when `SWW_RPROXY_DEFAULT_DISPOSITION` gave
-  `disposition`, and otherwise left out.
+- `waf_backend_no_answer`: `true` when
+  `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` gave `disposition`, and
+  otherwise left out.
 
 For example: