expr.head(0) silently returns 0 rows if other exprs have length of 1

[cmdlineluser]

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

import polars as pl

df = pl.DataFrame({"foo": [1, 2], "bar": [3, 4]})

df.select(pl.col.foo.head(0), pl.col.bar.head(1))
# shape: (0, 2)
# ┌─────┬─────┐
# │ foo ┆ bar │
# │ --- ┆ --- │
# │ i64 ┆ i64 │
# ╞═════╪═════╡
# └─────┴─────┘

Log output

No response

Issue description

If another height is > 1 - it errors as expected:

df.select(pl.col.foo.head(0), pl.col.bar.head(2))
# ComputeError: Series length 0 doesn't match the DataFrame height of 2

Expected behavior

ComputeError

Installed versions

--------Version info---------
Polars:               1.9.0
Index type:           UInt32
Platform:             macOS-13.6.1-arm64-arm-64bit
Python:               3.12.2 (main, Feb  6 2024, 20:19:44) [Clang 15.0.0 (clang-1500.1.0.2.5)]

----Optional dependencies----
adbc_driver_manager:  <not installed>
cloudpickle:          <not installed>
connectorx:           <not installed>
deltalake:            <not installed>
fastexcel:            <not installed>
fsspec:               <not installed>
gevent:               <not installed>
great_tables:         <not installed>
hvplot:               <not installed>
matplotlib:           <not installed>
nest_asyncio:         <not installed>
numpy:                1.26.4
openpyxl:             <not installed>
pandas:               2.2.1
pyarrow:              15.0.2
pydantic:             <not installed>
pyiceberg:            <not installed>
sqlalchemy:           <not installed>
torch:                <not installed>
xlsx2csv:             <not installed>
xlsxwriter:           <not installed>

[edwinvehmaanpera]

Culprit seems to be this:

polars/crates/polars-mem-engine/src/executors/projection_utils.rs

Lines 300 to 308 in 60a6465

	Ok(match series.len() {
	0 if df_height == 1 => series,
	1 => {
	if has_empty {
	polars_ensure!(df_height == 1,
	ComputeError: "Series length {} doesn't match the DataFrame height of {}",
	series.len(), df_height
	);
	series.slice(0, 0)

since df_height=max(series.len()) so with head(0)/ head(1) then df_height==1. I don't know what is special about df_height==1. This behaviour seems to have been introduced in #15903