- locationLimit, outcomeLimit, nearLocation now trim
  structuredContent.study and content[] identically; previously
  format() trimmed while the structured surface kept the full
  upstream record.
- locationLimit / outcomeLimit defaults flip default(10)/default(5)
  → .optional() (no cap). Callers depending on the silent trim must
  pass an explicit cap.
- Output schema folds the three echo fields into a single
  filtersApplied object that also carries upstream totals
  (totalLocations, locationsWithoutGeo, totalSecondaryOutcomes,
  totalOtherOutcomes) so callers can detect what was dropped.
- nearLocation annotates each surviving location with distanceMi
  in the structured surface as well as the rendered text.
- search_studies.format() no longer fabricates "Untitled" when
  briefTitle is missing — title segment omitted instead.
- Description copy tightened on search_studies, get_study_count,
  find_eligible, get_field_definitions, get_field_values.