move filtering logic into the coalescer

Author: alamb

datafusion/physical-plan/Cargo.toml

@@ -57,6 +57,7 @@ hashbrown = { workspace = true }
 indexmap = { workspace = true }
 itertools = { workspace = true, features = ["use_std"] }
 log = { workspace = true }
+num = "0.2.0"
 once_cell = "1.18.0"
 parking_lot = { workspace = true }
 pin-project-lite = "^0.2.7"