feat: extension point to update search index file name

[tiller1010]

https://werkbotstudios.teamwork.com/app/tasks/38739901

Summary

extension point to update search index file name

Testing Steps

• test with reed https://github.com/werkbot/reed-mfg-co/pull/222
• confirm multiple search index files can be created

Git Flow

• DO NOT delete "release/*" or "hotfix/*" branches after merging a PR. These are used to publish the next release, and they are deleted automatically.
• "Squash and merge" is good on "feature/*" into "develop"
• "Create a merge commit" is good on "release/*" or "hotfix/*" into "main"

[aletail]

This worked well!

Only thought, maybe for a future update - how could we generate the index files for each language automatically instead of switching the language in the cms and then running the search task.