feat(view): mint managed lanes to separate cross-mode content per stance (D2 W3-A)

Pure planLaneMinting decides which tracks hold >1 mode's content and which managed
lane each item lands on; view.cpp applies it (I_FREEMODE/I_NUMFIXEDLANES/P_LANENAME/
I_FIXEDLANE) under one undo block, driven off the auto-tag detection tick. Manual lanes
and their items are never touched. Load-time reconcile rebuilds ownership from durable
lane names before reapplying active-mode visibility.

src/main.cpp

@@ -224,6 +224,12 @@ static void OnTimer()
     // re-arm and the model restore ride the one authoritative load event.
     if (g_session.consumeLoadSignal()) {
         reasampler::bankPanelNotifyProjectLoaded();
+        // Reconcile the restored lane-ownership index against the live project's lanes
+        // FIRST (via REAPER's durable P_LANENAME — the cross-session source of truth),
+        // so a saved lane-split project's managed/manual classification is correct
+        // before the active mode's lane visibility is reapplied. Never re-mints, never
+        // mass-tags — it only records managed ownership recovered from lane names.
+        reasampler::reconcileManagedLanes(g_session.view(), nullptr);
         reasampler::applyMode(g_session.view(), g_session.view().activeModeId(), nullptr);
     }