Bake window: derived note lengths carry exact durations, not ladder rungs — a long take is no longer cut at 384 beats

Hold keeps its picker. Also: one home for the %-fold, duration-ordered Hold travel, and a corrupt tail degrades to absent rather than fabricating one.

src/shell/instrument/editor_platform.cpp

@@ -24,9 +24,11 @@ constexpr const wchar_t* kChildClassName = L"ReaSampler9000VstEditor";
 
 // The change-detection poll (WM_TIMER on the child window). A low-frequency UI-thread
 // timer: responsive enough that a recapture/ingest/assign refreshes within a bounded
-// cadence, yet cheap — three small ext-state reads per tick, coalescing many bumps
-// between ticks into one reload. 500 ms is a deliberate build-time residual. The id is a
-// per-window SetTimer id (any nonzero).
+// cadence, yet cheap — three small ext-state reads per tick in the steady state, coalescing
+// many bumps between ticks into one reload. Anything costlier a tick answers (the bake-Hold
+// predicate's bank parse) is memoized against its inputs, so keep it that way rather than
+// letting a per-tick full read back in. 500 ms is a deliberate build-time residual. The id is
+// a per-window SetTimer id (any nonzero).
 constexpr UINT_PTR kSyncTimerId = 1;
 constexpr UINT     kSyncTimerIntervalMs = 500;
 }  // namespace