Fix OIDC account linking by using SystemActor in LinkOidcAccountLive

- Add SystemActor to all Ash operations in LinkOidcAccountLive
- Enables user lookup, reload, and oidc_id linking during OIDC flow
- User is not yet logged in during linking, so SystemActor provides authorization

lib/mv_web/live/auth/link_oidc_account_live.ex

@@ -20,10 +20,13 @@ defmodule MvWeb.LinkOidcAccountLive do
 
   @impl true
   def mount(_params, session, socket) do
+    # Use SystemActor for authorization during OIDC linking (user is not yet logged in)
+    system_actor = Mv.Helpers.SystemActor.get_system_actor()
+
     with user_id when not is_nil(user_id) <- Map.get(session, "oidc_linking_user_id"),
          oidc_user_info when not is_nil(oidc_user_info) <-
            Map.get(session, "oidc_linking_user_info"),
-         {:ok, user} <- Ash.get(Mv.Accounts.User, user_id) do
+         {:ok, user} <- Ash.get(Mv.Accounts.User, user_id, actor: system_actor) do
       # Check if user is passwordless
       if passwordless?(user) do
         # Auto-link passwordless user immediately
@@ -46,9 +49,12 @@ defmodule MvWeb.LinkOidcAccountLive do
   end
 
   defp reload_user!(user_id) do
+    # Use SystemActor for authorization during OIDC linking (user is not yet logged in)
+    system_actor = Mv.Helpers.SystemActor.get_system_actor()
+
     Mv.Accounts.User
     |> Ash.Query.filter(id == ^user_id)
-    |> Ash.read_one!()
+    |> Ash.read_one!(actor: system_actor)
   end
 
   defp reset_password_form(socket) do
@@ -58,13 +64,16 @@ defmodule MvWeb.LinkOidcAccountLive do
   defp auto_link_passwordless_user(socket, user, oidc_user_info) do
     oidc_id = Map.get(oidc_user_info, "sub") || Map.get(oidc_user_info, "id")
 
+    # Use SystemActor for authorization (passwordless user auto-linking)
+    system_actor = Mv.Helpers.SystemActor.get_system_actor()
+
     case user.id
          |> reload_user!()
          |> Ash.Changeset.for_update(:link_oidc_id, %{
            oidc_id: oidc_id,
            oidc_user_info: oidc_user_info
          })
-         |> Ash.update() do
+         |> Ash.update(actor: system_actor) do
       {:ok, updated_user} ->
         Logger.info(
           "Passwordless account auto-linked to OIDC: user_id=#{updated_user.id}, oidc_id=#{oidc_id}"
@@ -187,6 +196,9 @@ defmodule MvWeb.LinkOidcAccountLive do
   defp link_oidc_account(socket, user, oidc_user_info) do
     oidc_id = Map.get(oidc_user_info, "sub") || Map.get(oidc_user_info, "id")
 
+    # Use SystemActor for authorization (user just verified password but is not yet logged in)
+    system_actor = Mv.Helpers.SystemActor.get_system_actor()
+
     # Update the user with the OIDC ID
     case user.id
          |> reload_user!()
@@ -194,7 +206,7 @@ defmodule MvWeb.LinkOidcAccountLive do
            oidc_id: oidc_id,
            oidc_user_info: oidc_user_info
          })
-         |> Ash.update() do
+         |> Ash.update(actor: system_actor) do
       {:ok, updated_user} ->
         # After successful linking, redirect to OIDC login
         # Since the user now has an oidc_id, the next OIDC login will succeed