fix(extractor): domain-aware entity ranking; v0.2.6

After v0.2.5 shipped, TMF652 Resource Ordering still extracted
'standby, alarm, available' as its lifecycle. Root cause was deeper
than v0.2.5 addressed: the TMF652 spec contains both ResourceOrder
(the API's primary entity) and Resource (a copy of TMF639's primary,
used as the ResourceRefOrValue base). Resource has more fields than
ResourceOrder, so the field-count-only entity ranking pushed
ResourceOrder past the top-4 cap, and lifecycle extraction then
walked Resource.resourceStatus and returned the inventory enum.

The fix adds domain-aware entity ranking. _extract_entities() now
accepts an optional api_id and uses (-domain_overlap, -field_count)
as the sort key. Domain stems come from API_REGISTRY (e.g. TMF652
'Resource Ordering' -> ['resource', 'order']), so ResourceOrder
scores 2 and beats Resource which scores 1.

After this fix TMF652 extracts the correct order states
(acknowledged, terminatedWithError, inProgress, done) directly
from the spec.

85 tests passing (76 existing + 9 isolation tests, 2 new for Bug 3).
Output schema unchanged - fully backwards-compatible patch release.
