feat: merge tuples from the AND-ed boolean expressions

src/frontend/sql/ast.rs

src/frontend/sql/ast/tests.rs

src/ir/expression.rs

src/ir/operator.rs

src/ir/operator/tests.rs

src/ir/transformation.rs

src/ir/transformation/merge_tuples.rs

src/ir/transformation/merge_tuples/tests.rs

src/ir/tree.rs

test_app/test/integration/api_test.lua