fix docstring and base params

Author: Tristan Dennis

malariagen_data/anoph/base_params.py

@@ -308,3 +308,11 @@ def validate_sample_selection_params(
     to select SNPs to be included
     """,
 ]
+
+overwrite: TypeAlias = Annotated[
+    bool,
+    """
+    A boolean indicating whether a previously written file with the same name ought
+    to be overwritten. Default is False.
+    """,
+]

malariagen_data/anoph/to_plink.py

@@ -62,7 +62,7 @@ def biallelic_snps_to_plink(
         region: base_params.regions,
         n_snps: base_params.n_snps,
         thin_offset: base_params.thin_offset = 0,
-        overwrite: bool = False,
+        overwrite: base_params.overwrite = False,
         sample_sets: Optional[base_params.sample_sets] = None,
         sample_query: Optional[base_params.sample_query] = None,
         sample_indices: Optional[base_params.sample_indices] = None,