Last-mile typecheck sweep: 3 small bugs

- GuideToolOngoingView classNames clause: classNames(..., 'chat.roomId'
  && 'cursor-pointer') — the property name was quoted so the literal
  string 'chat.roomId' was always-truthy. Unquote to read the actual
  chat.roomId field.
- NavigatorRoomSettingsModTabView: UserProfileIconView userName={ user.userId }
  put a number into the string-typed userName prop; the right prop for
  a numeric id is userId.
- WiredExtraVariableEchoView resolvedVariableEntries: the inline
  fallback-entry literal at the bottom of the useMemo got its kind
  field widened to string (instead of the 'custom' literal needed by
  IWiredVariablePickerEntry). Lift it into a typed const + rename to
  namedFallback to avoid the shadowing of the upstream
  createFallbackVariableEntry result.

src/components/navigator/views/room-settings/NavigatorRoomSettingsModTabView.tsx

@@ -58,7 +58,7 @@ export const NavigatorRoomSettingsModTabView: FC<NavigatorRoomSettingsTabViewPro
                         {
                             return (
                                 <Flex key={ index } shrink alignItems="center" gap={ 1 } overflow="hidden">
-                                    <UserProfileIconView userName={ user.userId } />
+                                    <UserProfileIconView userId={ user.userId } />
                                     <Text pointer grow onClick={ event => setSelectedUserId(user.userId) }> { user.userName }</Text>
                                 </Flex>
                             );