For modules that fully implement Stripe Connect, i.e. that sign requests with their own API keys, there was no way to pass contextual data to the proxy when making those requests. This commit addresses the issue by populating the `proxy_data` param present in all proxy's routes' signatures with an extendable `dict`. task-2917229 closes odoo/odoo#96279 X-original-commit: 5df308c58e02c9ca3287c124c0df4e359817ce16 Signed-off-by: Antoine Vandevenne (anv) <anv@odoo.com>