i18n slice 1 (A.2-A.4, A.6): narrowed English mask, marker coverage test, English retrieval stems, parse timing

Five v0.247.0 fixtures re-captured from UNCONVERTED v0.246.0 (89dd3e94) because their
one-word Hungarian data values had to become multi-word; two new cases (backups_tier_due,
app_info_installable) captured the same way — the coverage test found both gaps.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/web/server.go

@@ -307,7 +307,9 @@ func (s *Server) loadTemplates() {
 		for name, fn := range s.localeFuncs(lang) {
 			funcs[name] = fn
 		}
+		start := time.Now()
 		t, st, err := parseTemplateSet(b, lang, funcs)
+		took := time.Since(start)
 		if err != nil {
 			panic(fmt.Errorf("templates (%s): %w", lang, err))
 		}
@@ -316,7 +318,7 @@ func (s *Server) loadTemplates() {
 			s.logger.Printf("[INFO] [web] i18n: %s template set shows Hungarian for %d markers (keys not yet translated)", lang, len(st.FellBack))
 		}
 		if s.isDebug() {
-			s.logger.Printf("[DEBUG] [web] loadTemplates: lang=%s loaded %d templates, %d markers expanded", lang, len(t.Templates()), st.Markers)
+			s.logger.Printf("[DEBUG] [web] loadTemplates: lang=%s loaded %d templates, %d markers expanded in %s", lang, len(t.Templates()), st.Markers, took)
 		}
 	}
 	s.tmpl = s.tmplByLang[i18n.Default]