[Bug]: cannot share to remote users with "show_federated_shares_to_trusted_servers_as_internal" set to true

[maximelehericy]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

The PR #55080 introduces a config switch to show shares to trusted servers in the internal share section.

However, enabling this setting prevents shares to federated cloudIDs to be created:

when something is typed in the external share section, the following request

GET /ocs/v2.php/apps/files_sharing/api/v1/sharees?format=json&itemType=folder&search=tata%40cloud.net&lookup=true&perPage=25&shareType%5B%5D=4&shareType%5B%5D=6&shareType%5B%5D=9

returns the following response:

{
  "ocs": {
    "meta": {
      "status": "ok",
      "statuscode": 200,
      "message": "OK"
    },
    "data": {
      "exact": {
        "users": [],
        "groups": [],
        "remotes": [
          {
            "label": "tata (cloud.net)",
            "uuid": "tata",
            "name": "tata",
            "value": {
              "shareType": 6,
              "shareWith": "tata@cloud.net",
              "server": "cloud.net",
              "isTrustedServer": false
            }
          }
        ],
        "remote_groups": [],
        "emails": [
          {
            "label": "tata@cloud.net",
            "uuid": "tata@cloud.net",
            "value": {
              "shareType": 4,
              "shareWith": "tata@cloud.net"
            }
          }
        ],
        "circles": [],
        "rooms": [],
        "lookup": []
      },
      "users": [],
      "groups": [],
      "remotes": [],
      "remote_groups": [],
      "emails": [],
      "lookup": [],
      "circles": [],
      "rooms": [],
      "lookupEnabled": true
    }
  }
}

In the external share section, the result

 "remotes": [
          {
            "label": "tata (cloud.net)",
            "uuid": "tata",
            "name": "tata",
            "value": {
              "shareType": 6,
              "shareWith": "tata@cloud.net",
              "server": "cloud.net",
              "isTrustedServer": false
            }
          }
        ],

is filtered out.

Steps to reproduce

1. spawn a vanilla nextcloud 31.0.11
2. set show_federated_shares_to_trusted_servers_as_internal to true
3. enter a federated cloud ID in the external share section

Expected behavior

I should be able to share to remote federated user.

Nextcloud Server version

31

Operating system

Other

PHP engine version

None

Web server

None

Database engine version

None

Is this bug present after an update or on a fresh install?

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

List of activated Apps

Nextcloud Signing status

Nextcloud Logs

Additional info

No response