fix(config): translate hyphens to underscores in sub-category guard variable names

__fish_config_op_enabled built the sub-category override variable name by
concatenating the tag's slug verbatim, e.g. __fish_config_op_integrations_window-mgmt.
Fish variable names cannot contain hyphens, so any hyphenated sub-category
slug (14 of the 24 in the taxonomy) silently could never be overridden --
an unset such variable safely fell through via set -q, but attempting to
set it always errored with "invalid variable name", masking the defect
since no prior smoke test exercised an explicit sub-category-level toggle.
The registry tag itself (as authored in # COMPONENT headers and the
taxonomy docs) stays hyphenated; only the derived fish variable name is
translated.

functions/__fish_config_op_enabled.fish

@@ -61,7 +61,7 @@ function __fish_config_op_enabled --description 'Guard for an opinionated compon
     for tag in $tags
         set -l parts (string split -m 1 -- / $tag)
         set -l category_var "__fish_config_op_$parts[1]"
-        set -l subcat_var "__fish_config_op_$parts[1]_$parts[2]"
+        set -l subcat_var "__fish_config_op_$parts[1]_"(string replace -a -- '-' '_' $parts[2])
         __fish_config_op_cascade $category_var $subcat_var
         or return 1
     end