Circle shares not synced when adding first member from a new remote instance

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New members from an instance with no previous members don't get existing circle shares synced in federated environment.

Steps to reproduce

1. setup federation environment with two Nextcloud instances (e.g. nc_1 + nc_2)
2. on nc_1 as bob:

• create test_team and check "Allow federated members"
• create test_folder and share with test_team
• add john from nc_2 (john@nc_2)

3. on nc_2 as john:

• navigate to files > "All files"
• notice how shared folder does not appear

note: if there's already another member from nc_2 on test_team and has access to test_folder, adding a new member does show the resource correctly for them.

Expected behaviour

• john should see test_folder among his files has the resource was shared with a team he belongs to
• entries should be created on oc_circles_mount and oc_circles_mountpoint for given resource on nc_2

Actual behaviour

• john does not see test_folder among his files.
• entries are not created on oc_circles_mount and oc_circles_mountpoint for given resource on nc_2

Server configuration

Web server: Apache/Nginx

Database: MySQL/Maria/SQLite/PostgreSQL

PHP version: 8.5/8.4/8.3

Nextcloud version: Nextcloud 36.0.0 dev

If you have access to your command line run e.g.:
sudo -u www-data php occ config:list system
from within your Nextcloud installation folder

Browser

Browser name: Firefox/Chrome/Safari/…

Browser version: 124/125/…

Operating system: Windows/Ubuntu/Mac/…

Insert your browser log here, this could for example include:
a) The javascript console log
b) The network log
c) ...

Start by reproducing the two-instance federation setup described in the issue, then trace the path taken when the first remote member is added to a circle. Inspect why oc_circles_mount and oc_circles_mountpoint entries are not created on the remote instance; done means john sees test_folder and both entries are created in the new-instance case.