feat: Add shared helper functions for actor handling

- Add Mv.Helpers module with ash_actor_opts/1 helper
- Add current_actor/1 with @spec to LiveHelpers
- Add ash_actor_opts/1 delegate and submit_form/3 wrapper to LiveHelpers
- Standardize actor access pattern across LiveViews

lib/mv_web/live_helpers.ex

@@ -71,7 +71,41 @@ defmodule MvWeb.LiveHelpers do
       actor = current_actor(socket)
       members = Membership.list_members!(actor: actor)
   """
+  @spec current_actor(Phoenix.LiveView.Socket.t()) :: Mv.Accounts.User.t() | nil
   def current_actor(socket) do
     socket.assigns[:current_user] || socket.assigns.current_user
   end
+
+  @doc """
+  Converts an actor to Ash options list for authorization.
+  Returns empty list if actor is nil.
+
+  Delegates to `Mv.Helpers.ash_actor_opts/1` for consistency across the application.
+
+  ## Examples
+
+      opts = ash_actor_opts(actor)
+      Ash.read(query, opts)
+  """
+  @spec ash_actor_opts(Mv.Accounts.User.t() | nil) :: keyword()
+  defdelegate ash_actor_opts(actor), to: Mv.Helpers
+
+  @doc """
+  Submits an AshPhoenix form with consistent actor handling.
+
+  This wrapper ensures that actor is always passed via `action_opts`
+  in a consistent manner across all LiveViews.
+
+  ## Examples
+
+      case submit_form(form, params, actor) do
+        {:ok, resource} -> # success
+        {:error, form} -> # validation errors
+      end
+  """
+  @spec submit_form(AshPhoenix.Form.t(), map(), Mv.Accounts.User.t() | nil) ::
+          {:ok, Ash.Resource.t()} | {:error, AshPhoenix.Form.t()}
+  def submit_form(form, params, actor) do
+    AshPhoenix.Form.submit(form, params: params, action_opts: ash_actor_opts(actor))
+  end
 end