* Feature: match fuzzy terms in place inside the parsed query
Fuzzy matching was a separate clause OR'd in above the query: a flat bag
of the query's words, re-parsed through tantivy's own parser, blended
beside the exact clause. Nothing around a term reached it, so a fielded
term fuzzed across every default field, a filter did not constrain it, and
an exclusion had to be hoisted back over the whole blend to stop the
clause re-admitting what the query had just excluded.
Widen each leaf where it sits instead, through emit()'s rewrite_leaf hook,
so fielding, negation, AND, REQUIRE and positive filters constrain the
fuzzy match exactly as they constrain the exact one. Each of a leaf's
words becomes a Fuzzy leaf on the leaf's own field, boosted to 0.1, beside
the leaf and any CJK alternative it already had.
* Hello?
* Feature: parse advanced search with whoosh-compat and delete the hand-written translator
* Don't cover these, they exist for defensive, but there's no other current diagnostic
* A mix of more no cover and tests
* Route SCHEMA_FIELD_MISSING into an error, not an HTTP 400
Trenton H