T2: realtime capture tail trimming

Auto/Manual/Off tail handling for realtime track-tap capture. Auto scans
recorded PCM backward for last frame above -72 dB and truncates the wav
header-aware (8 s cap); Manual pads a fixed tail; Off is byte-identical.
wav_trim rejects WAVE_FORMAT_EXTENSIBLE with non-float SubFormat GUID.

src/main.cpp

@@ -596,13 +596,20 @@ static void RunCaptureRealtimeTrack()
         return;
     }
 
+    // The tail mode is the SAME panel setting the offline capture actions read (the
+    // docked bank panel's toggle). Realtime honors it via a parallel path: the backend
+    // records a generous window past the range end, then trims by PCM decay-scan (T2 /
+    // capture-tail.md §The realtime path) — it does NOT drive RENDER_*. Default None
+    // keeps realtime exact-bounds / byte-identical to today.
+    const reasampler::TailSetting tail = reasampler::bankPanelTailSetting();
+
     reasampler::CaptureRequest req;
     req.sourceMode   = reasampler::SourceMode::SelectedTracks;  // realtime track scope
     req.startSeconds = src.startSeconds;                        // exact bounds — no rounding
     req.endSeconds   = src.endSeconds;
     req.wetDry       = 1.0;                                     // fully wet (post-fader tap)
-    req.tailMode     = reasampler::TailMode::None;              // realtime tail is T2; exact bounds here
-    req.tailMs       = 0.0;
+    req.tailMode     = tail.mode;           // None / Auto / Manual, from the panel toggle
+    req.tailMs       = tail.manualMs;       // Manual-only (pre-clamped); ignored for None/Auto
     req.sampleRate   = 0;                                       // follow project rate
     req.channelCount = 2;
     req.bitDepth     = reasampler::WavBitDepth::Float32;
@@ -623,8 +630,15 @@ static void RunCaptureRealtimeTrack()
     // completion across ticks (UI stays responsive).
     g_rtCaptureProject = EnumProjects(-1, nullptr, 0);
     g_rtCapture = std::move(st);
-    ShowConsoleMsg("ReaSampler: realtime capture started — recording in the "
-                   "background; the bank updates when it reaches the range end.\n");
+    // With a tail mode the recorded window runs PAST the range end (Auto: +8 s then
+    // decay-trim; Manual: +the set length), so the completion note names the window,
+    // not just the range end.
+    const char* doneWhen =
+        (tail.mode == reasampler::TailMode::None)
+            ? "the bank updates when it reaches the range end."
+            : "the bank updates after the extra tail window (past the range end).";
+    ShowConsoleMsg((std::string("ReaSampler: realtime capture started — recording in "
+                                "the background; ") + doneWhen + "\n").c_str());
 }
 
 // Cancels the in-flight realtime capture on demand (bindable action). Force-terminates