feat: increase dict decompression throughput (#1032)

If we are canonicalizing the dictionary, we will likely canonicalize all
the values. For formats like bitpacking this substantially improves
throughput. In particular, we spend a lot of time preparing the indices
for chunked decoding and then pplying the patches.

encodings/dict/src/array.rs

@@ -67,7 +67,8 @@ impl ArrayTrait for DictArray {}
 
 impl IntoCanonical for DictArray {
     fn into_canonical(self) -> VortexResult<Canonical> {
-        take(self.values(), self.codes())?.into_canonical()
+        let canonical_values: Array = self.values().into_canonical()?.into();
+        take(canonical_values, self.codes())?.into_canonical()
     }
 }