fix(ontology): change trackId from single-select to string type

AT-30548 specifies that trackId content is not predefined and can be
any string containing letters and/or numbers. Changed trackId attribute
type from single-select (which requires predefined options) to string.

Also fixed:
- SingleSelectAttribute: Only convert numeric values to strings when
  all options are numeric, preventing false-positive ATTRIBUTE_VALUE
  errors for non-numeric option sets
- test_automatedtrain_has_safety_critical_classes: Updated expected
  classes to match actual ontology (track, signal, buffer_stop, switch)

Author: crorry-dev