Fix meta derivation for from_lists

[hombit]

There was a bug in the code, because pack assumed that given empty array is a "flat" array, not "lists" array

[github-actions]

Before [e1e1993] <v0.3.2>	After [ee40ee8]	Ratio	Benchmark (Parameter)
821±2ms	828±6ms	1.01	benchmarks.NestedFrameQuery.time_run
137M	137M	1	benchmarks.NestedFrameAddNested.peakmem_run
270±3ms	269±0.9ms	1	benchmarks.NestedFrameAddNested.time_run
139M	139M	1	benchmarks.NestedFrameQuery.peakmem_run
135M	135M	1	benchmarks.NestedFrameReduce.peakmem_run
282±2ms	282±1ms	1	benchmarks.NestedFrameReduce.time_run

Click here to view all benchmarks.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.45%. Comparing base (e1e1993) to head (67c36e7).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #83   +/-   ##
=======================================
  Coverage   95.45%   95.45%           
=======================================
  Files           9        9           
  Lines         242      242           
=======================================
  Hits          231      231           
  Misses         11       11           

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