feat(lanes): clearLane archives the active feature before resetting (B)

server/lib/lanes.js

@@ -334,10 +334,16 @@ function recordDetection(id, { nodeId, signal } = {}) {
  * never be advanced past.
  */
 function clearLane(id) {
+  // Opt-in: only a lane that has activated a feature has anything to archive.
+  // Requiring the module here (not at file top) avoids a require cycle —
+  // lane-features.js itself requires this file for lanesLib.getLane/setStage.
+  require("./lane-features").archiveActiveFeature(id);
+
   db.prepare(
     `UPDATE lanes SET stage = 'idle', stage_since = ?, status = 'idle', gate_decision = NULL,
        ci_status = NULL, needs_action = NULL, stages = '{}', notes = NULL, run_id = NULL,
        detected_stage = NULL, detected_signal = NULL, detected_at = NULL,
+       active_feature_id = NULL,
        updated_at = ? WHERE id = ?`
   ).run(nowIso(), nowIso(), id);
   return getLane(id);