Page type-check: types for what the API sends, and for S (#235)

web/src/types.ts mirrors FeedRow, EntryRow, EncRow, /api/me and PopularRow; types only, so
swc strips it and it is not in build.mjs's list.

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

web/src/util.ts

@@ -215,7 +215,7 @@ function folderArt(f,kids){
 function nav(on){ $('#sidebar').classList.toggle('open',on); $('#scrim').hidden=!on; }
 
 /* ---------------- state ---------------- */
-const S = {
+const S: State = {
   feeds:[],
   // Which feed (or place) and which tab were open last time, so a refresh lands back where
   // you were instead of jumping to the first feed alphabetically.