feat(announcements): add admin/user announcement system

Implements announcements end-to-end (admin CRUD + read status, user list + mark read) with OR-of-AND targeting. Also breaks the ent<->service import cycle by moving schema-facing constants/targeting into a new domain package.

backend/ent/user/user.go

@@ -51,6 +51,8 @@ const (
 	EdgeSubscriptions = "subscriptions"
 	// EdgeAssignedSubscriptions holds the string denoting the assigned_subscriptions edge name in mutations.
 	EdgeAssignedSubscriptions = "assigned_subscriptions"
+	// EdgeAnnouncementReads holds the string denoting the announcement_reads edge name in mutations.
+	EdgeAnnouncementReads = "announcement_reads"
 	// EdgeAllowedGroups holds the string denoting the allowed_groups edge name in mutations.
 	EdgeAllowedGroups = "allowed_groups"
 	// EdgeUsageLogs holds the string denoting the usage_logs edge name in mutations.
@@ -91,6 +93,13 @@ const (
 	AssignedSubscriptionsInverseTable = "user_subscriptions"
 	// AssignedSubscriptionsColumn is the table column denoting the assigned_subscriptions relation/edge.
 	AssignedSubscriptionsColumn = "assigned_by"
+	// AnnouncementReadsTable is the table that holds the announcement_reads relation/edge.
+	AnnouncementReadsTable = "announcement_reads"
+	// AnnouncementReadsInverseTable is the table name for the AnnouncementRead entity.
+	// It exists in this package in order to avoid circular dependency with the "announcementread" package.
+	AnnouncementReadsInverseTable = "announcement_reads"
+	// AnnouncementReadsColumn is the table column denoting the announcement_reads relation/edge.
+	AnnouncementReadsColumn = "user_id"
 	// AllowedGroupsTable is the table that holds the allowed_groups relation/edge. The primary key declared below.
 	AllowedGroupsTable = "user_allowed_groups"
 	// AllowedGroupsInverseTable is the table name for the Group entity.
@@ -335,6 +344,20 @@ func ByAssignedSubscriptions(term sql.OrderTerm, terms ...sql.OrderTerm) OrderOp
 	}
 }
 
+// ByAnnouncementReadsCount orders the results by announcement_reads count.
+func ByAnnouncementReadsCount(opts ...sql.OrderTermOption) OrderOption {
+	return func(s *sql.Selector) {
+		sqlgraph.OrderByNeighborsCount(s, newAnnouncementReadsStep(), opts...)
+	}
+}
+
+// ByAnnouncementReads orders the results by announcement_reads terms.
+func ByAnnouncementReads(term sql.OrderTerm, terms ...sql.OrderTerm) OrderOption {
+	return func(s *sql.Selector) {
+		sqlgraph.OrderByNeighborTerms(s, newAnnouncementReadsStep(), append([]sql.OrderTerm{term}, terms...)...)
+	}
+}
+
 // ByAllowedGroupsCount orders the results by allowed_groups count.
 func ByAllowedGroupsCount(opts ...sql.OrderTermOption) OrderOption {
 	return func(s *sql.Selector) {
@@ -432,6 +455,13 @@ func newAssignedSubscriptionsStep() *sqlgraph.Step {
 		sqlgraph.Edge(sqlgraph.O2M, false, AssignedSubscriptionsTable, AssignedSubscriptionsColumn),
 	)
 }
+func newAnnouncementReadsStep() *sqlgraph.Step {
+	return sqlgraph.NewStep(
+		sqlgraph.From(Table, FieldID),
+		sqlgraph.To(AnnouncementReadsInverseTable, FieldID),
+		sqlgraph.Edge(sqlgraph.O2M, false, AnnouncementReadsTable, AnnouncementReadsColumn),
+	)
+}
 func newAllowedGroupsStep() *sqlgraph.Step {
 	return sqlgraph.NewStep(
 		sqlgraph.From(Table, FieldID),