site: tag pages include finds; find-only tags get pages

Tag pages are now generated from the union of entry and find tags —
1,179 tags that existed only on finds (most tag links on find pages)
previously 404'd. Tagged finds render in a compact secondary "Finds"
list below the entry grid, keeping the editorial tier on top. Find-only
tag pages with fewer than 3 finds are noindexed until they fill out.
Tag feeds stay entries-only; the RSS pill and autodiscovery link only
render where a feed exists. Category pages unchanged (finds have no
category).

Claude-Session: https://claude.ai/code/session_01WZaczDJjL3xZ3u5spsN5AL

astro.config.mjs

@@ -136,7 +136,7 @@ const feedSlashShim = {
   name: 'feed-trailing-slash-dev-shim',
   apply: 'serve',
   configureServer(server) {
-    server.middlewares.use((req, res, next) => {
+    server.middlewares.use((req, _res, next) => {
       if (/^\/(tags|categories)\/[^/]+\/rss\.xml$/.test(req.url)) req.url += '/';
       next();
     });