Issue Summary

migratedFromConnect setting in the app manifest only makes Forge custom content searchable by Connect key, but not bye Forge key that contradicts the documentation: https://developer.atlassian.com/platform/adopting-forge-from-connect/migrate-custom-content/.

Steps to Reproduce

1. Create a Connect app with a custom content type xyz and install it to a Confluence instance.
2. Try to run a search query by the Connect custom content type: /wiki/rest/api/search?cql=type="ac:my-app:xyz". It returns a successful response.
3. Migrate the app to Forge. Define custom content xyz under confluence:customContent module. Set migratedFromConnect to true.
4. Install the app to a Confluence instance. It'll replace the Connect app.
5. Try to run the same search query: /wiki/rest/api/search?cql=type="ac:my-app:xyz". It returns a successful response.
6. Try to run a search query for Forge custom content type: /wiki/rest/api/search?cql=type="forge:app-id:app-env-id:xyz".

Expected Results

Both searches return a successful response.

Actual Results

The search query for the Forge custom content type returns the error:

{
    "statusCode": 400,
    "data": {
        "authorized": true,
        "valid": true,
        "errors": [],
        "successful": true
    },
    "message": "com.atlassian.confluence.api.service.exceptions.api.BadRequestException: Unsupported value for type, got : forge:app-id:app-env-id:xyz, expected one of : [space, user, page, blogpost, comment, attachment, database, whiteboard, slide, embed, folder, com.atlassian.confluence.extra.team-calendars:calendar-content-type, com.atlassian.confluence.extra.team-calendars:space-calendars-view-content-type, ac:my-app:xyz]"
} 

Workaround

Continue using Connect custom content type in search.