gql2sql compiler

TODO

- [x] support std aggregation
- [x] support stdp aggregation
- [x] support var aggregation
- [x] support varp aggregation
- [x] support like filter
- [x] support not like filter
- [x] support ilike filter
- [x] support not ilike filter
- [x] support total-count agg
- [x] support enum filters
- [x] ~~remove implicit variant filtering~~
- [x] support coalesce details to empty array when no data

- [x] support nested summaries for collections
- [x] support nested summaries for entities
- [x] support summaries over enums

- [ ] support variant summaries
- [ ] support nested variant relations

- [ ] support summary filters
- [ ] support summary ordering
- [ ] support nested limit
- [ ] support date filters