Unifying Projections with File Reader Execs

### Is your feature request related to a problem or challenge?

While implementing [that projection pushdown rule](https://github.com/apache/arrow-datafusion/pull/8073), a case caught my attention. In some cases, projection and file readers (such as CsvExec) can be positioned sequentially, and the sole function of the Projection is to assign aliases. In these cases, couldn't this task be handled by the readers? They can perform projections internally, and if they could also define aliases, it would simplify such plans.

### Describe the solution you'd like

While trying to eliminate projections after readers, if the projection makes aliasing, that new name can be used in the reader schema and other related outputs. The only exception is an evaluation in the projection, which cannot be operated during the read operation.

### Describe alternatives you've considered

_No response_

### Additional context

_No response_

Start with the projection pushdown rule in PR 8073 and the file-reader execution plans such as CsvExec. Determine how eligible projections and aliases could be represented in reader schemas and related outputs while leaving computed expressions in a Projection. Done means sequential reader-plus-aliasing-Projection plans are eliminated without moving unsupported evaluations into the read operation.

Written by the indexing model from the issue text.