feat(member): back the overview with a keyset-paginated :overview read action

lib/membership/member.ex

@@ -266,6 +266,15 @@ defmodule Mv.Membership.Member do
       accept [:vereinfacht_contact_id]
     end
 
+    # Keyset-paginated read for the member overview. Filters and sort are
+    # composed onto the query by `MvWeb.MemberLive.Index.OverviewQuery`; this
+    # action only enables keyset pagination with a unique `id` tie-breaker so
+    # pages never skip or duplicate rows.
+    read :overview do
+      description "Keyset-paginated member overview read"
+      pagination keyset?: true, default_limit: 50, required?: false
+    end
+
     # Action to handle fuzzy search on specific fields
     read :search do
       argument :query, :string, allow_nil?: true
@@ -279,27 +288,7 @@ defmodule Mv.Membership.Member do
         threshold =
           Ash.Query.get_argument(query, :similarity_threshold) || @default_similarity_threshold
 
-        if is_binary(q) and String.trim(q) != "" do
-          q2 = String.trim(q)
-          # Sanitize for LIKE patterns (escape % and _), limit length to 100 chars
-          q2_sanitized = sanitize_search_query(q2)
-          pat = "%" <> q2_sanitized <> "%"
-
-          # Build search filters grouped by search type for maintainability
-          # Priority: FTS > Substring > Custom Fields > Fuzzy Matching
-          # Note: FTS and fuzzy use q2 (unsanitized), LIKE-based filters use pat (sanitized)
-          fts_match = build_fts_filter(q2)
-          substring_match = build_substring_filter(q2_sanitized, pat)
-          custom_field_match = build_custom_field_filter(pat)
-          fuzzy_match = build_fuzzy_filter(q2, threshold)
-
-          query
-          |> Ash.Query.filter(
-            expr(^fts_match or ^substring_match or ^custom_field_match or ^fuzzy_match)
-          )
-        else
-          query
-        end
+        apply_fuzzy_search_filter(query, q, threshold)
       end
     end
 
@@ -738,6 +727,13 @@ defmodule Mv.Membership.Member do
     end
   end
 
+  aggregates do
+    # Alphabetically-first group name, used to sort the overview by group DB-side.
+    # Mirrors the previous in-memory "first group name" sort key; members with no
+    # groups yield nil (sorted last ascending via NULLS LAST).
+    min :first_group_name, :groups, :name
+  end
+
   # Define identities for upsert operations
   identities do
     identity :unique_email, [:email]
@@ -1212,6 +1208,43 @@ defmodule Mv.Membership.Member do
     end
   end
 
+  @doc """
+  Applies the same fuzzy/full-text search filter as the `:search` action as a
+  plain filter on the given query, without switching the query's read action.
+
+  Used by the overview query builder so search composes with the `:overview`
+  keyset-paginated read action instead of replacing it.
+  """
+  @spec apply_overview_search(Ash.Query.t(), String.t() | nil) :: Ash.Query.t()
+  def apply_overview_search(query, q) do
+    apply_fuzzy_search_filter(query, q || "", @default_similarity_threshold)
+  end
+
+  # Shared by the `:search` action and `apply_overview_search/2`.
+  defp apply_fuzzy_search_filter(query, q, threshold) do
+    if is_binary(q) and String.trim(q) != "" do
+      q2 = String.trim(q)
+      # Sanitize for LIKE patterns (escape % and _), limit length to 100 chars
+      q2_sanitized = sanitize_search_query(q2)
+      pat = "%" <> q2_sanitized <> "%"
+
+      # Build search filters grouped by search type for maintainability
+      # Priority: FTS > Substring > Custom Fields > Fuzzy Matching
+      # Note: FTS and fuzzy use q2 (unsanitized), LIKE-based filters use pat (sanitized)
+      fts_match = build_fts_filter(q2)
+      substring_match = build_substring_filter(q2_sanitized, pat)
+      custom_field_match = build_custom_field_filter(pat)
+      fuzzy_match = build_fuzzy_filter(q2, threshold)
+
+      Ash.Query.filter(
+        query,
+        expr(^fts_match or ^substring_match or ^custom_field_match or ^fuzzy_match)
+      )
+    else
+      query
+    end
+  end
+
   # ============================================================================
   # Search Input Sanitization
   # ============================================================================

lib/membership/membership.ex

@@ -45,6 +45,7 @@ defmodule Mv.Membership do
     resource Mv.Membership.Member do
       define :create_member, action: :create_member
       define :list_members, action: :read
+      define :overview_members, action: :overview
       define :update_member, action: :update_member
       define :destroy_member, action: :destroy
     end