Fix custom cast count selection

README.md

@@ -375,8 +375,13 @@ Supported constraints:
 - `cast` or `requires`: `women_only`, `men_only`, `mixed`, `has_women`,
   `has_men`, `solo`, `couple`, `threesome`, `group`
 
-If an exact subcategory is not compatible with `women_count` and `men_count`,
-the node raises a clear error instead of generating an impossible prompt.
+If an exact subcategory has a larger minimum cast size than the current
+`women_count` and `men_count`, the node raises the effective cast count to that
+minimum instead of failing. The original and effective counts are recorded in
+`metadata_json.cast_count_adjustment`. Other impossible cast constraints still
+raise a clear error instead of generating an impossible prompt.
+When both cast counts are `0`, custom category selection treats the effective
+configured cast as one adult woman so random filtering still has a valid cast.
 
 Use the `subcategory` dropdown to select either `random` or an exact
 `Main category / Subcategory` path. Exact paths override the `category` dropdown,