feat: Allow to use repeat_by with (nested) lists and structs

[borchero]

Resolves #21151.

This PR introduces logic to use repeat_by with columns of arbitrarily nested lists and structs, extending the current functionality beyond primitive & binary types.

The implementation was a little hairy as the arbitrary inner dtypes of lists and structs requires plenty of dynamic type conversions. This is the first time I did something like this in polars; very happy about any feedback to make the code simpler/more efficient :)

That being said... it works flawlessly with all examples that I tried 😄

---

Very minimal performance test:

import polars as pl
import numpy as np


### Primitive ###
df_primitive = df = pl.DataFrame({
    "a": np.random.randint(0, 100, size=100_000),
    "b": np.random.randint(0, 5, size=100_000)
})
# %%timeit
df_primitive.select(pl.col("a").repeat_by(pl.col("b")))
# >> 2.33 ms ± 53.8 μs per loop


### List ###
df_list = pl.DataFrame({
    "a": np.random.randint(0, 100, size=1_000_000).reshape(100_000, 10),
    "b": np.random.randint(0, 5, size=100_000)
}, schema={"a": pl.List(pl.Int64), "b": pl.Int64})
# %%timeit
df_list.select(pl.col("a").repeat_by(pl.col("b")))
# >> 12.3 ms ± 185 μs per loop

[codecov]

Codecov Report

Attention: Patch coverage is 64.82085% with 108 lines in your changes missing coverage. Please review.

Project coverage is 79.81%. Comparing base (e8e0295) to head (428db60).
Report is 13 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-arrow/src/array/mutable_dyn/make.rs	45.33%	41 Missing ⚠️
...es/polars-arrow/src/legacy/array/nested/struct_.rs	62.85%	26 Missing ⚠️
...rates/polars-arrow/src/legacy/array/nested/list.rs	52.27%	21 Missing ⚠️
crates/polars-ops/src/chunked_array/repeat_by.rs	77.27%	10 Missing ⚠️
crates/polars-arrow/src/legacy/array/mod.rs	86.84%	5 Missing ⚠️
...rates/polars-arrow/src/io/avro/read/deserialize.rs	71.42%	2 Missing ⚠️
crates/polars-arrow/src/legacy/array/nested/mod.rs	92.85%	2 Missing ⚠️
...rates/polars-arrow/src/array/mutable_dyn/nested.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #21206      +/-   ##
==========================================
- Coverage   79.88%   79.81%   -0.08%     
==========================================
  Files        1593     1597       +4     
  Lines      227649   228071     +422     
  Branches     2600     2600              
==========================================
+ Hits       181860   182027     +167     
- Misses      45192    45447     +255     
  Partials      597      597              

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[borchero]

@alexander-beedie (since you reacted to a comment in the issue 😄) -- is there anything I can do to aid review here? I'd love to make use of this feature with the next polars release 😇

[borchero]

@ritchie46 do you have any thoughts about this? Would love to drive this change along :)