feat: add node stale/delete config

closes: #93

db/sqlc/mock/querier.go

@@ -57,6 +57,20 @@ func (mr *MockQuerierMockRecorder) DeleteOldChannelIATAs(ctx, lastHeard any) *go
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "DeleteOldChannelIATAs", reflect.TypeOf((*MockQuerier)(nil).DeleteOldChannelIATAs), ctx, lastHeard)
 }
 
+// DeleteOldNodes mocks base method.
+func (m *MockQuerier) DeleteOldNodes(ctx context.Context, lastSeen pgtype.Timestamptz) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "DeleteOldNodes", ctx, lastSeen)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// DeleteOldNodes indicates an expected call of DeleteOldNodes.
+func (mr *MockQuerierMockRecorder) DeleteOldNodes(ctx, lastSeen any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "DeleteOldNodes", reflect.TypeOf((*MockQuerier)(nil).DeleteOldNodes), ctx, lastSeen)
+}
+
 // DeleteOldPackets mocks base method.
 func (m *MockQuerier) DeleteOldPackets(ctx context.Context, lastHeardAt pgtype.Timestamptz) error {
 	m.ctrl.T.Helper()

db/sqlc/querier.go

@@ -14,6 +14,14 @@ import (
 type Querier interface {
 	// Keeps the channel IATA filter in step with packet retention.
 	DeleteOldChannelIATAs(ctx context.Context, lastHeard pgtype.Timestamptz) error
+	// Deletes nodes not seen since the given cutoff. node_iatas and node_neighbors cascade-
+	// delete via FK. Excludes nodes referenced by observer_owners.owner_node_id -- that FK has
+	// no ON DELETE action, so deleting one directly would fail the whole statement anyway, and
+	// an operator manually recorded ownership for that node, so leave it alone even if stale.
+	// known_routes.node_ids is a plain UUID[] with no FK; a deleted node's id can be left
+	// dangling in old routes there, but ReconfirmTask already prunes stale/ambiguous routes
+	// periodically and will clean those up on its own schedule.
+	DeleteOldNodes(ctx context.Context, lastSeen pgtype.Timestamptz) error
 	// Deletes packets and their observations older than the given cutoff.
 	// packet_observations cascade-delete via FK.
 	DeleteOldPackets(ctx context.Context, lastHeardAt pgtype.Timestamptz) error

db/sqlc/queries.sql.go

@@ -22,6 +22,24 @@ func (q *Queries) DeleteOldChannelIATAs(ctx context.Context, lastHeard pgtype.Ti
 	return err
 }
 
+const deleteOldNodes = `-- name: DeleteOldNodes :exec
+DELETE FROM nodes
+WHERE last_seen < $1
+  AND id NOT IN (SELECT owner_node_id FROM observer_owners WHERE owner_node_id IS NOT NULL)
+`
+
+// Deletes nodes not seen since the given cutoff. node_iatas and node_neighbors cascade-
+// delete via FK. Excludes nodes referenced by observer_owners.owner_node_id -- that FK has
+// no ON DELETE action, so deleting one directly would fail the whole statement anyway, and
+// an operator manually recorded ownership for that node, so leave it alone even if stale.
+// known_routes.node_ids is a plain UUID[] with no FK; a deleted node's id can be left
+// dangling in old routes there, but ReconfirmTask already prunes stale/ambiguous routes
+// periodically and will clean those up on its own schedule.
+func (q *Queries) DeleteOldNodes(ctx context.Context, lastSeen pgtype.Timestamptz) error {
+	_, err := q.db.Exec(ctx, deleteOldNodes, lastSeen)
+	return err
+}
+
 const deleteOldPackets = `-- name: DeleteOldPackets :exec
 DELETE FROM packets WHERE last_heard_at < $1
 `