Fix removeContainedEntries (led to incorrect distances for constructors when the type name itself was also matched)

Make sure usage entries are sorted after collecting parent usages of constructors, fields and class members

- Adapt to performance enhancements in Database.Native returning [!!]
  from getEntries
- Add type_synonyms index array to avoid walking through entire database
  on unification queries

Early fail for bad matches of small queries (e.g. one-letter queries from the VSCode plugin) to speed up ranking

Use unambiguous [TVAssignment] instead of Unifier to figure out required context to avoid variable clashes (e.g. 'select :: [a] Int -> a' would require Array [] [] instead of Array [] a)