[I] Support projections for metadata table scans [iceberg-rust]

["Perseus (via GitHub)" <gi...@apache.org>]

Perseus opened a new issue, #3391:
URL: https://github.com/apache/iceberg-rust/issues/3391

   ### Is your feature request related to a problem or challenge?
   
   Iceberg metadata tables like snapshots currently [scan/project every column ](https://github.com/apache/iceberg-rust/blob/main/crates/iceberg/src/inspect/snapshots.rs#L111-L122). This leads to unneccessary overhead if the caller only requests a few columns.
   
   ### Describe the solution you'd like
   
   Similar to normal tables, we could implement the ability to specify columns as part of the scan-building process. I looked through a couple of other libraries for reference, and it looks like the [Java Iceberg  ](https://github.com/apache/iceberg/blob/main/core/src/main/java/org/apache/iceberg/SnapshotsTable.java#L51-L87) library does something similar - using the existing 'Scan' infrastructure and extending it to metadata tables as well.
   
   Today's API looks like
   ```rust
     table
        .inspect()
        .snapshots()
        .scan()
        .await?
   ```
   
   A future API could look something like
   
   ```rust
     table
       .inspect()
       .snapshots()
       .select(["operation", "snapshot_id"])
       .scan()
       .await?
   ```
   
   This suggestion is merely illustrative, I think that any abstraction/configuration that supports the core feature is good.
   
   ### Willingness to contribute
   
   I would be willing to contribute to this feature with guidance from the Iceberg Rust community


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