Align the 2.13 API reference across repositories (#722)

* Align the 2.13 API reference across repositories

- Name the two DELETE /custom_object_instances operations after the
  identifier each takes: deleteCustomObjectInstancesById for the path
  with {id}, deleteCustomObjectInstancesByExternalId for the one that
  takes external_id.
- Describe list and other data attribute types with oneOf in
  create_data_attribute_request and update_data_attribute_request, as
  2.14 does. List options are objects with a value key.
- Write "Unix timestamp", and "Unix timestamp in seconds" in the search
  operator tables.
- Use example.com instead of twitter.com in the POST /messages and
  social_profile examples.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

* Describe the IP allowlist values of previous_state and new_state

The activity log metadata fields previous_state and new_state also carry
`enabled` or `disabled` for IP allowlist changes, not only `idle` or
`occupied` for occupancy changes.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

* Show the occupancy events in the activity log example

Add an admin_occupancy_state_change and an admin_occupancy_setting_change
entry to the GET /admins/activity_logs response example, so it shows
previous_state, new_state, threshold_minutes, last_activity_at, auto,
setting_type and changes. The state change is recorded by the system,
so its performed_by ip is `unknown`.

The before and after values in activity_log_metadata.changes get an
example each, and their descriptions say they take the setting's own
type. They keep no `type`, because the value can be an integer, a
boolean, a string or a list depending on the setting.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

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Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: markdennis22