[Bug] The UnawareAppendTableCompactionCoordinator may leave some small files can not be compacted

### Search before asking

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

### Paimon version

1.0

### Compute Engine

all

### Minimal reproduce step

.

### What doesn't meet your expectations?

when compact in batch, there is no `age` maintained, we should compact the remaining files

### Anything else?

_No response_

### Are you willing to submit a PR?

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

Locate UnawareAppendTableCompactionCoordinator and read its batch-compaction logic, focusing on how file age is maintained and how remaining small files are selected. Reproduce the reported case if possible, then verify that small files left after batch compaction are eventually eligible for compaction.

Written by the indexing model from the issue text.