Currently, the Limit operator does not combine small pages into larger 
ones; it simply passes them along, except for chunking pages larger than
the limit. This change integrates EstimatesRowSize into Limit and
adjusts it to emit larger pages. As a result, pages up to twice the
pageSize may be emitted, which is preferable to emitting undersized
pages. This should reduce the number of transport requests and responses
between clusters or coordinator-data nodes for queries without TopN or
STATS when target shards produce small pages due to their size or highly
selective filters.

Currently, the Limit operator does not combine small pages into larger 
ones; it simply passes them along, except for chunking pages larger than
the limit. This change integrates EstimatesRowSize into Limit and
adjusts it to emit larger pages. As a result, pages up to twice the
pageSize may be emitted, which is preferable to emitting undersized
pages. This should reduce the number of transport requests and responses
between clusters or coordinator-data nodes for queries without TopN or
STATS when target shards produce small pages due to their size or highly
selective filters.

Currently, the Limit operator does not combine small pages into larger 
ones; it simply passes them along, except for chunking pages larger than
the limit. This change integrates EstimatesRowSize into Limit and
adjusts it to emit larger pages. As a result, pages up to twice the
pageSize may be emitted, which is preferable to emitting undersized
pages. This should reduce the number of transport requests and responses
between clusters or coordinator-data nodes for queries without TopN or
STATS when target shards produce small pages due to their size or highly
selective filters.

This PR reverts #128531.

With #128531, the Limit operator was updated to combine smaller pages 
into a larger page to reduce overhead, such as the number of exchange 
requests. However, this has a significant implication: the combined
larger page does not retain the attributes of the blocks from the
smaller pages. For example, if the smaller pages have ordinal-based
BytesRef blocks, the larger page will not. This can cause a significant
slowdown if subsequent operators have optimizations for ordinal-based
blocks. The Enrich operator has such optimizations, and our benchmarks
have shown this performance regression.

One possible solution to reduce the regression is to set a threshold 
(e.g., 1000 rows), above which the Limit operator would pass the page
along without combining. However, even with a threshold of 1000, the
performance regression does not go away completely. Alternatively, we
could allow exchange requests to return multiple pages (up to the page
size limit). To minimize risk, this PR reverts the previous change, and
we will reintroduce a new change later

This PR reverts elastic#128531.

With elastic#128531, the Limit operator was updated to combine smaller pages 
into a larger page to reduce overhead, such as the number of exchange 
requests. However, this has a significant implication: the combined
larger page does not retain the attributes of the blocks from the
smaller pages. For example, if the smaller pages have ordinal-based
BytesRef blocks, the larger page will not. This can cause a significant
slowdown if subsequent operators have optimizations for ordinal-based
blocks. The Enrich operator has such optimizations, and our benchmarks
have shown this performance regression.

One possible solution to reduce the regression is to set a threshold 
(e.g., 1000 rows), above which the Limit operator would pass the page
along without combining. However, even with a threshold of 1000, the
performance regression does not go away completely. Alternatively, we
could allow exchange requests to return multiple pages (up to the page
size limit). To minimize risk, this PR reverts the previous change, and
we will reintroduce a new change later

This PR reverts elastic#128531.

With elastic#128531, the Limit operator was updated to combine smaller pages 
into a larger page to reduce overhead, such as the number of exchange 
requests. However, this has a significant implication: the combined
larger page does not retain the attributes of the blocks from the
smaller pages. For example, if the smaller pages have ordinal-based
BytesRef blocks, the larger page will not. This can cause a significant
slowdown if subsequent operators have optimizations for ordinal-based
blocks. The Enrich operator has such optimizations, and our benchmarks
have shown this performance regression.

One possible solution to reduce the regression is to set a threshold 
(e.g., 1000 rows), above which the Limit operator would pass the page
along without combining. However, even with a threshold of 1000, the
performance regression does not go away completely. Alternatively, we
could allow exchange requests to return multiple pages (up to the page
size limit). To minimize risk, this PR reverts the previous change, and
we will reintroduce a new change later