refactor(capture): expose offline tail as docked-panel toggle

Replace the ...-with-tail variant actions with a pure tail_control module +
a docked-panel footer toggle (Off/Auto/Manual) read by CAPTURE_ITEM/TRACK.
Default None (byte-identical); Manual fixed 2s, in-memory session lifetime.
Tail mechanism unchanged; retired the variant ids.

src/main.cpp

@@ -69,12 +69,17 @@ static std::vector<gaccel_register_t>  g_captureAccels;
 //   * CAPTURE_MASTER and CAPTURE_MASTER_REALTIME — the master offline scope and the
 //     master realtime action are REMOVED (capture is now item + track only; realtime
 //     taps the selected track). Their shipped ids are retired so old keybindings clear.
+//   * CAPTURE_ITEM_TAIL and CAPTURE_TRACK_TAIL — the former per-action tail variants
+//     are REMOVED; tail is now a panel-setting toggle, not a paired action. Retired so
+//     old keybindings clear.
 static const char* const kRetiredCaptureCmdStrings[] = {
     "CEREBELLUM_REASAMPLER_CAPTURE_TRACKS_WET",
     "CEREBELLUM_REASAMPLER_CAPTURE_ITEMS_WET",
     "CEREBELLUM_REASAMPLER_CAPTURE_RAZOR_WET",
     "CEREBELLUM_REASAMPLER_CAPTURE_MASTER",
     "CEREBELLUM_REASAMPLER_CAPTURE_MASTER_REALTIME",
+    "CEREBELLUM_REASAMPLER_CAPTURE_ITEM_TAIL",
+    "CEREBELLUM_REASAMPLER_CAPTURE_TRACK_TAIL",
 };
 
 // Command id for "ReaSampler: toggle bank panel" (M5). FOREVER-STABLE string.
@@ -505,13 +510,19 @@ static void RunCapture(const reasampler::CaptureActionDef& def)
         return;
     }
 
+    // The tail mode is a PANEL SETTING (docked bank panel's toggle), not a per-action
+    // variant: the plain capture actions apply whatever the panel is set to. Default
+    // is None (exact bounds / byte-identical to today) until the user opts in via the
+    // toggle. tailMs is meaningful only for Manual and is pre-clamped by the panel.
+    const reasampler::TailSetting tail = reasampler::bankPanelTailSetting();
+
     reasampler::CaptureRequest req;
     req.sourceMode   = reasampler::sourceModeForScope(def.scope);
     req.startSeconds = src.startSeconds;    // exact bounds — no rounding
     req.endSeconds   = src.endSeconds;
     req.wetDry       = 1.0;                 // wet post the FX left enabled by the scope
-    req.tailMode     = def.tailMode;        // None (exact bounds) or Auto ("…with tail" variant)
-    req.tailMs       = 0.0;                 // Manual-only; no Manual action yet (future config/UI)
+    req.tailMode     = tail.mode;           // None / Auto / Manual, from the panel toggle
+    req.tailMs       = tail.manualMs;       // Manual-only (clamped); ignored for None/Auto
     req.sampleRate   = 0;                   // follow project rate
     req.channelCount = 2;
     req.bitDepth     = reasampler::WavBitDepth::Float32;  // deterministic, no dither