feat(bank_panel): docked bank grid with LICE waveform thumbnails (M5 Wave A)

Docked SWELL window toggled by a new action, drawing the current bank as
per-sample min/max thumbnails (PCM_source + peaks) with an in-memory cache.
Pure grid-layout/cache-key math in bank_grid (tested). Renames peaks::Sample
-> AudioSample to avoid colliding with bank_model::Sample.

src/resource.h

@@ -0,0 +1,10 @@
+#pragma once
+// resource.h — dialog/control ids for ReaSampler's SWELL dialogs.
+//
+// Shared by resource.rc (Windows resource compiler) and, on macOS/Linux, by the
+// SWELL resgen-generated source (see CLAUDE.md §SWELL dialog resources). Keep the
+// numeric ids stable and unique across the extension.
+
+// The docked bank panel (M5). A bare owner-drawn child dialog: it carries no
+// controls — bank_panel.cpp paints the whole client area with LICE.
+#define IDD_BANK_PANEL 1000