feat(12.2-01): add deferred:purge, its daily framework schedule and relation child hooks

- deferred:purge [--days] in lagoon.RuntimeCommands (purge_days, default 5)
- lagoon.FrameworkSchedule entry at purge_at (default 03:00, empty disables)
- conga prepends framework entries as summercms.lagoon[i]:<command>
- pact.Relation{Before,After}{Create,Update,Delete} optional hooks
- lagoon, conga and pact READMEs, scheduling and setup docs

modules/pact/capabilities.go

@@ -391,6 +391,51 @@ type RelationBeforeLink interface {
 	RelationBeforeLink(ctx context.Context, relation string, parent, related any, pivot map[string]any) error
 }
 
+// The six relation child hooks below are optional admin-controller
+// capabilities for a relation manager that creates, updates or deletes
+// related records. Before hooks run inside the child write's transaction
+// before the row is written; After hooks run after the write and before the
+// commit. parent is the loaded parent record, or a fresh record with a zero
+// key while the parent is not saved yet (deferral). child is the related
+// record being written. An error rolls the write back and the admin API
+// answers its opaque lifecycle error.
+
+// RelationBeforeCreate optionally runs before a related record is created
+// through a relation manager.
+type RelationBeforeCreate interface {
+	RelationBeforeCreate(ctx context.Context, relation string, parent, child any) error
+}
+
+// RelationAfterCreate optionally runs after a related record is created
+// through a relation manager, before the commit.
+type RelationAfterCreate interface {
+	RelationAfterCreate(ctx context.Context, relation string, parent, child any) error
+}
+
+// RelationBeforeUpdate optionally runs before a related record is updated
+// through a relation manager.
+type RelationBeforeUpdate interface {
+	RelationBeforeUpdate(ctx context.Context, relation string, parent, child any) error
+}
+
+// RelationAfterUpdate optionally runs after a related record is updated
+// through a relation manager, before the commit.
+type RelationAfterUpdate interface {
+	RelationAfterUpdate(ctx context.Context, relation string, parent, child any) error
+}
+
+// RelationBeforeDelete optionally runs before a related record is deleted
+// through a relation manager.
+type RelationBeforeDelete interface {
+	RelationBeforeDelete(ctx context.Context, relation string, parent, child any) error
+}
+
+// RelationAfterDelete optionally runs after a related record is deleted
+// through a relation manager, before the commit.
+type RelationAfterDelete interface {
+	RelationAfterDelete(ctx context.Context, relation string, parent, child any) error
+}
+
 // FilterScope is the model capability a config_filter scope name may call.
 // FilterScopes is the exact, case-sensitive set of names; request text never
 // selects a method outside that set.