Add admin location editing

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

handlers.go

@@ -578,6 +578,24 @@ func (s *Server) handleUpdateDescription(w http.ResponseWriter, r *http.Request)
 	http.Redirect(w, r, fmt.Sprintf("/e/%s/admin/%s", event.Slug, event.AdminToken), http.StatusSeeOther)
 }
 
+func (s *Server) handleUpdateLocation(w http.ResponseWriter, r *http.Request) {
+	event := s.authorizeAdmin(w, r, false)
+	if event == nil {
+		return
+	}
+
+	r.Body = http.MaxBytesReader(w, r.Body, 8*1024)
+	r.ParseForm()
+	location := sanitize(r.FormValue("location"), maxFieldLen)
+
+	s.q.UpdateEventLocation(r.Context(), db.UpdateEventLocationParams{
+		Location: location,
+		ID:       event.ID,
+	})
+
+	http.Redirect(w, r, fmt.Sprintf("/e/%s/admin/%s", event.Slug, event.AdminToken), http.StatusSeeOther)
+}
+
 func (s *Server) handleCreateSlot(w http.ResponseWriter, r *http.Request) {
 	event := s.authorizeAdmin(w, r, false)
 	if event == nil {