[Bug] first_value semantic conflict

### Search before asking

- [X] I searched in the [issues](https://github.com/apache/paimon/issues) and found nothing similar.

### Paimon version

0.8

### Compute Engine

Flink

### Minimal reproduce step

I have read this issues: https://github.com/apache/paimon/issues/3020

I discovered this phenomenon：
```
CREATE TABLE T (
k INT,
a INT,
b VARCHAR,
c VARCHAR,
d VARCHAR,
PRIMARY KEY (k) NOT ENFORCED)
WITH ('merge-engine'='aggregation',
'fields.b.aggregate-function'='first_value',
'fields.c.aggregate-function'='first_non_null_value',
'fields.d.aggregate-function'='first_not_null_value',
'sequence.field' = 'a'
);
```
```
INSERT INTO T VALUES (1, 4, '4', '4', '4')
INSERT INTO T VALUES (1, 2, '2', '2', '2')
INSERT INTO T VALUES (1, 3, '3', '3', '3')
```
The result is `[1, 4, 2, 2, 2]` , as expected

If I manually trigger a compaction before the third insert, like:
```
INSERT INTO T VALUES (1, 4, '4', '4', '4')
INSERT INTO T VALUES (1, 2, '2', '2', '2')
CALL sys.compact('default.t', '', '', '', 'sink.parallelism=4')
INSERT INTO T VALUES (1, 3, '3', '3', '3')
```
The result is `[1, 4, 3, 3, 3]` , and there is a semantic problem.
For local debugging, in this case, there are only two values merged ​​([1, 3, 3, 3, 3], [1, 4, 2, 2, 2]) when querying.
It seems that after compaction, the previous sequence information was lost.

### What doesn't meet your expectations?

The Doc. description is vague：


I'm not sure if there's something wrong with my understanding. Should the oldest sequence be maintained? Otherwise the compaction will lead to inconsistent first_value semantics

### Anything else?

_No response_

### Are you willing to submit a PR?

- [X] I'm willing to submit a PR!

Reproduce the SQL sequence with aggregation fields using first_value, first_non_null_value, and first_not_null_value, then repeat it with CALL sys.compact before the third insert. Compare the results and the retained sequence information before and after compaction; the issue is resolved when compaction preserves consistent first_value semantics or the documented behavior is corrected.

Written by the indexing model from the issue text.