scan_delta fails silently when using the new streaming table

[roykim98]

Checks

• I have checked that this issue has not already been reported.
• I have confirmed this bug exists on the latest version of Polars.

Reproducible example

df = pl.scan_delta("delta/").collect() # returns DataFrame with rows
df = pl.scan_delta("delta/").collect(streaming=True) # returns DataFrame with rows
df = pl.scan_delta("delta/").collect(new_streaming=True) # returns empty DataFrame

Log output

Issue description

Taking any delta table, the new streaming engine silently returns empty DataFrames whereas the old streaming engine and no streaming engine otherwise works.

I tried with many types of Delta Tables, the result is deterministic on 1.23.

Expected behavior

Expect to have non-empty dataframes.

Installed versions

--------Version info---------
Polars:              1.23.0
Index type:          UInt32
Platform:            macOS-15.3.1-arm64-arm-64bit-Mach-O
Python:              3.13.1 (main, Dec  5 2024, 14:28:32) [Clang 15.0.0 (clang-1500.3.9.4)]
LTS CPU:             False

----Optional dependencies----
Azure CLI            <not installed>
adbc_driver_manager  <not installed>
altair               <not installed>
azure.identity       <not installed>
boto3                <not installed>
cloudpickle          3.1.1
connectorx           <not installed>
deltalake            0.22.3
fastexcel            <not installed>
fsspec               <not installed>
gevent               <not installed>
google.auth          2.38.0
great_tables         <not installed>
matplotlib           3.10.0
numpy                2.2.3
openpyxl             <not installed>
pandas               2.2.3
...
sqlalchemy           2.0.38
torch                <not installed>
xlsx2csv             <not installed>
xlsxwriter           <not installed>