Drupal Custom Schema Override Module

• Provides a custom JSON-LD field in the metatag sidebar that overrides schema_metatag structured data output when populated.
• Requires the use of the Drupal Metatag module along with the Drupal Schema Metatag module
• Metatag only shows a group on a bundle's edit form if that bundle has no visible-groups restriction configured, or if the group is explicitly listed in its restriction. Bundles with no restriction already show all groups, including "Schema JSON Override," and need no action.
• If a site has already restricted a bundle's visible groups (admin/config/search/metatag/settings) before this module is installed, hook_install() enables "Schema JSON Override" for those bundles automatically as a one-time pass. Run drush config:export after installing/updating this module so that change is captured in the repo -- otherwise a later drush config:import will silently revert it. This sync only runs at install; it does not run again for bundles created afterwards.
• As a safety net, the module also reports a warning on the Status Report (and during drush updb) listing any restricted bundle still missing the group -- e.g. if the post-install export was skipped, or a later config import reverted it. Enable it manually on the settings form, then run drush config:export, to clear the warning.