chore: movs display name helper to won helper module

lib/mv_web/helpers/member_helpers.ex

@@ -0,0 +1,64 @@
+defmodule MvWeb.Helpers.MemberHelpers do
+  @moduledoc """
+  Helper functions for member-related operations in the web layer.
+
+  Provides utilities for formatting and displaying member information.
+  """
+
+  alias Mv.Membership.Member
+
+  @doc """
+  Returns a display name for a member.
+
+  Combines first_name and last_name if available, otherwise falls back to email.
+  This ensures that members without names still have a meaningful display name.
+
+  ## Examples
+
+      iex> member = %Member{first_name: "John", last_name: "Doe", email: "john@example.com"}
+      iex> MvWeb.Helpers.MemberHelpers.display_name(member)
+      "John Doe"
+
+      iex> member = %Member{first_name: nil, last_name: nil, email: "john@example.com"}
+      iex> MvWeb.Helpers.MemberHelpers.display_name(member)
+      "john@example.com"
+
+      iex> member = %Member{first_name: "John", last_name: nil, email: "john@example.com"}
+      iex> MvWeb.Helpers.MemberHelpers.display_name(member)
+      "John"
+  """
+  def display_name(%Member{} = member) do
+    name_parts =
+      [member.first_name, member.last_name]
+      |> Enum.reject(&blank?/1)
+      |> Enum.map_join(" ", &String.trim/1)
+
+    if name_parts == "" do
+      member.email
+    else
+      name_parts
+    end
+  end
+
+  @doc """
+  Checks if a value is blank (nil, empty string, or only whitespace).
+
+  ## Examples
+
+      iex> MvWeb.Helpers.MemberHelpers.blank?(nil)
+      true
+
+      iex> MvWeb.Helpers.MemberHelpers.blank?("")
+      true
+
+      iex> MvWeb.Helpers.MemberHelpers.blank?("   ")
+      true
+
+      iex> MvWeb.Helpers.MemberHelpers.blank?("John")
+      false
+  """
+  def blank?(nil), do: true
+  def blank?(""), do: true
+  def blank?(value) when is_binary(value), do: String.trim(value) == ""
+  def blank?(_), do: false
+end