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GH-32884: [C++] Add ordered aggregation (#34311)

This PR implements "Segmented Aggregation" to the existing aggregation
node to improve aggregation on ordered data.

A segment group is defined as "a continuous chunk of data that have the
same segment key value. e.g, if the input data looks like

```
[0, 0, 0, 1, 2, 2] 
```

Then there are three segments `[0, 0, 0]` `[1]` `[2, 2]`

(Note the "group" in "segment group" here is added to differentiate from
"segment", which is defined as "a continuous chunk of data with in a
ExecBatch")

Segment aggregation can be used to replace existing hash aggregation in
the case that data are ordered. The benefit of this is
(1) We can output aggregation result earlier (as soon as a segment group
is fully consumed).
(2) We only need to hold partial aggregation for one segment group to
reduce memory usage.

See https://issues.apache.org/jira/browse/ARROW-17642

Replaces #14352
* Closes: #32884

Follow ups
=======
* #34475 
* #34529

---------

Co-authored-by: Li Jin <ice.xelloss@gmail.com>