panel: align page URLs, titles, and headings

Settings moves to /settings with a 308 redirect from /account; domains, Status, Users, and user forms get matching browser titles and h1 text; backup page title reflects domain import.

Co-Authored-By: Composer <noreply@cursor.com>
Co-authored-by: Cursor <cursoragent@cursor.com>

internal/web/handlers/handlers_users.go

@@ -121,7 +121,11 @@ func (h *Handlers) renderUserForm(w http.ResponseWriter, r *http.Request, status
 		return
 	}
 	data := h.pageBase(r)
-	data["Title"] = "SelfPost — user"
+	if userID != 0 {
+		data["Title"] = "SelfPost — edit user"
+	} else {
+		data["Title"] = "SelfPost — create user"
+	}
 	data["Active"] = "users"
 	data["UserID"] = userID
 	data["Domains"] = domains