We currently have two value types, `Value` and `OwnedValue`. The
original thinking was that `Value` is external type and `OwnedValue` is
internal type. However, this just results in unnecessary transformation
between the types as data crosses the Limbo library boundary.
Let's just follow SQLite here and consolidate on a single value type
(where `sqlite3_value` is just an alias for the internal `Mem` type).
The way this will eventually work is that we can have bunch of
pre-allocated `OwnedValue` objects in `ProgramState` and basically
return a reference to them all the way to the application itself, which
extracts the actual value.
Move result row to `ProgramState` to mimic what SQLite does where `Vdbe`
struct has a `pResultRow` member. This makes it easier to deal with result
lifetime, but more importantly, eventually lazily parse values at the edges of
the API.
## Purpose of this PR
- Implement `close()` method for `LimboStatement`(+`JDBC4Statement`) and
`LimboResultSet`(+ `JDBC4ResultSet`)
## Changes
- Add `consumeAll` method in `LimboResultSet`
- Implement `close()` methods
- Because `JDBC4Statement` has longer lifecycle in compared to
`LimboStatement`, we manage different `close` fields(`LimboStatement` is
created when first `execute` method is called on `JDBC4Statemenet`)
## Reference
- [Issue](https://github.com/tursodatabase/limbo/issues/615)
Closes#799
