refactor: Redirect stderr to log file for easier debugging (#133)

This PR refactors the meta comparison scripts in the workflow to improve
debugging capabilities. The change redirects stderr to the log file
specified by `snakemake.log[0]`. By capturing error messages in the log
file, it becomes easier to diagnose and troubleshoot issues during
workflow execution.

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## Summary by CodeRabbit

- **New Features**
- Enhanced error tracking by redirecting standard error output to a
designated log file.

workflow/scripts/compare_diffexp.py

@@ -2,6 +2,9 @@
 import polars as pl
 import polars.selectors as cs
 import altair as alt
+import sys
+
+sys.stderr = open(snakemake.log[0], "w")
 
 diffexp_x = pl.from_pandas(pyreadr.read_r(snakemake.input[0])[None]).lazy()
 diffexp_y = pl.from_pandas(pyreadr.read_r(snakemake.input[1])[None]).lazy()

workflow/scripts/compare_enrichment.py

@@ -1,6 +1,9 @@
 import polars as pl
 import polars.selectors as cs
 import altair as alt
+import sys
+
+sys.stderr = open(snakemake.log[0], "w")
 
 diffexp_x = pl.read_csv(snakemake.input[0], separator="\t").lazy()
 diffexp_y = pl.read_csv(snakemake.input[1], separator="\t").lazy()

workflow/scripts/compare_pathways.py

@@ -1,6 +1,9 @@
 import polars as pl
 import polars.selectors as cs
 import altair as alt
+import sys
+
+sys.stderr = open(snakemake.log[0], "w")
 
 diffexp_x = pl.read_csv(snakemake.input[0], separator="\t").lazy()
 diffexp_y = pl.read_csv(snakemake.input[1], separator="\t").lazy()