Keep the metrics entry at the top of Completed Steps

Model: opus-5-5

TODO.md

@@ -30,6 +30,15 @@ P2: security: per-origin rate limiting
 
 # Completed Steps
 
+- 2026-10-15 the request metrics are labelled by route, not by path (closes
+  #254): their `handler` label was each request's path, so every new path, a 404
+  or an encrypted URL, added series to the Prometheus registry that were never
+  removed, and `/metrics` listed every encrypted URL's token. The label is now
+  the pattern of the chi route the request matches, such as `/v1/image/*`, or
+  `unmatched` for a request that matches none: one the router answers 404 or
+  405, or a CORS preflight. The metrics library takes the label before the
+  request is routed, so the metrics middleware asks the router which route
+  matches.
 - 2026-10-15 expired negative cache rows are removed on a schedule (closes
   #244): the row of a failed fetch, which makes pixa answer 502 for that source
   URL for 5 minutes, was deleted only when the same URL was requested again
@@ -41,15 +50,6 @@ P2: security: per-origin rate limiting
   expired. The goroutine runs with the disk cache disabled
   (`cache_max_bytes: 0`) too, where it does nothing else, as the negative cache
   is used either way.
-- 2026-10-15 the request metrics are labelled by route, not by path (closes
-  #254): their `handler` label was each request's path, so every new path, a 404
-  or an encrypted URL, added series to the Prometheus registry that were never
-  removed, and `/metrics` listed every encrypted URL's token. The label is now
-  the pattern of the chi route the request matches, such as `/v1/image/*`, or
-  `unmatched` for a request that matches none: one the router answers 404 or
-  405, or a CORS preflight. The metrics library takes the label before the
-  request is routed, so the metrics middleware asks the router which route
-  matches.
 - 2026-10-15 a cached variant is served while its source URL is in the negative
   cache (closes #245): `Get` checked the negative cache before the variant
   cache, so once a fetch of the source failed, as one does when another variant