feat: implement automatic cycle generation for members

- Add CycleGenerator module with advisory lock mechanism
- Add SetMembershipFeeStartDate change for auto-calculation
- Extend Settings with include_joining_cycle and default_membership_fee_type_id
- Add scheduled job skeleton for future Oban integration

lib/membership/member.ex

@@ -80,7 +80,7 @@ defmodule Mv.Membership.Member do
       argument :user, :map, allow_nil?: true
 
       # Accept member fields plus membership_fee_type_id (belongs_to FK)
-      accept @member_fields ++ [:membership_fee_type_id]
+      accept @member_fields ++ [:membership_fee_type_id, :membership_fee_start_date]
 
       change manage_relationship(:custom_field_values, type: :create)
 
@@ -101,6 +101,30 @@ defmodule Mv.Membership.Member do
       change Mv.EmailSync.Changes.SyncUserEmailToMember do
         where [changing(:user)]
       end
+
+      # Auto-calculate membership_fee_start_date if not manually set
+      # Requires both join_date and membership_fee_type_id to be present
+      change Mv.MembershipFees.Changes.SetMembershipFeeStartDate
+
+      # Trigger cycle generation after member creation
+      # Only runs if membership_fee_type_id is set
+      # Note: Cycle generation runs asynchronously to not block the action,
+      # but in test environment it runs synchronously for DB sandbox compatibility
+      change after_action(fn _changeset, member, _context ->
+               if member.membership_fee_type_id && member.join_date do
+                 if Application.get_env(:mv, :env) == :test do
+                   # Run synchronously in test environment for DB sandbox compatibility
+                   Mv.MembershipFees.CycleGenerator.generate_cycles_for_member(member.id)
+                 else
+                   # Run asynchronously in other environments
+                   Task.start(fn ->
+                     Mv.MembershipFees.CycleGenerator.generate_cycles_for_member(member.id)
+                   end)
+                 end
+               end
+
+               {:ok, member}
+             end)
     end
 
     update :update_member do
@@ -114,7 +138,7 @@ defmodule Mv.Membership.Member do
       argument :user, :map, allow_nil?: true
 
       # Accept member fields plus membership_fee_type_id (belongs_to FK)
-      accept @member_fields ++ [:membership_fee_type_id]
+      accept @member_fields ++ [:membership_fee_type_id, :membership_fee_start_date]
 
       change manage_relationship(:custom_field_values, on_match: :update, on_no_match: :create)
 
@@ -141,6 +165,34 @@ defmodule Mv.Membership.Member do
       change Mv.EmailSync.Changes.SyncUserEmailToMember do
         where [changing(:user)]
       end
+
+      # Auto-calculate membership_fee_start_date when membership_fee_type_id is set
+      # and membership_fee_start_date is not already set
+      change Mv.MembershipFees.Changes.SetMembershipFeeStartDate do
+        where [changing(:membership_fee_type_id)]
+      end
+
+      # Trigger cycle generation when membership_fee_type_id changes
+      # Note: Cycle generation runs asynchronously to not block the action,
+      # but in test environment it runs synchronously for DB sandbox compatibility
+      change after_action(fn changeset, member, _context ->
+               fee_type_changed =
+                 Ash.Changeset.changing_attribute?(changeset, :membership_fee_type_id)
+
+               if fee_type_changed && member.membership_fee_type_id && member.join_date do
+                 if Application.get_env(:mv, :env) == :test do
+                   # Run synchronously in test environment for DB sandbox compatibility
+                   Mv.MembershipFees.CycleGenerator.generate_cycles_for_member(member.id)
+                 else
+                   # Run asynchronously in other environments
+                   Task.start(fn ->
+                     Mv.MembershipFees.CycleGenerator.generate_cycles_for_member(member.id)
+                   end)
+                 end
+               end
+
+               {:ok, member}
+             end)
     end
 
     # Action to handle fuzzy search on specific fields