fix: restore waveform symmetry about the midline, cut deck_values' link to the bank model, and unit-test the column arithmetic

The waveform column's vertical extents move to pure component_geometry so the shared
primitive stops being untested; PlaySeconds hoists into a header-only play_seconds target.

src/core/instrument/map/sample_map.h

@@ -14,6 +14,7 @@
 
 #include "core/model/bank_book.h"       // BankBook::deserialize (shared bank JSON parse)
 #include "core/instrument/engine/play_params.h"  // SampleData, SampleLoop, PlayParams
+#include "core/instrument/map/play_seconds.h"    // PlaySeconds (the stored seconds value layer)
 #include "core/capture/wav_codec.h"        // parseWavLayout, extractFloatFrames (shared WAV parse)
 
 namespace reasampler::instrument::map {
@@ -134,81 +135,7 @@ std::vector<AudioSample> downmixToMono(const std::vector<AudioSample>& interleav
 std::vector<AudioSample> extractChannel(const std::vector<AudioSample>& interleaved,
                                         int channelCount, int which);
 
-// --- Stored (wall-clock SECONDS) play params ----------------------------------
-//
-// Daniel's standing ruling: no hardcoded sample rate anywhere in the program. The
-// instrument stores/edits wall-clock performance times (AHDSR A/H/D/R, pitch-env A/D) as
-// SECONDS, rate-free; the engine receives FRAMES resolved from the LIVE sample rate at
-// build. Quantities anchored to the source file's timeline (start point, loop points,
-// Trigger %-length + fades) stay in source frames/fractions, carried through unchanged
-// (TriggerParams reused verbatim).
-//
-// The stored AHDSR times (seconds). sustainLevel is dimensionless (0..1), not a time; the
-// three curve exponents are dimensionless too (curve_law.h owns their domain).
-struct AdsrSeconds {
-    double attackSeconds  = 0.003;  // tier-0 default
-    double holdSeconds    = 0.0;
-    double decaySeconds   = 0.0;
-    double sustainLevel   = 1.0;
-    double releaseSeconds = 0.060;  // tier-0 default
-    double attackCurve    = util::kCurveNeutral;
-    double decayCurve     = util::kCurveNeutral;
-    double releaseCurve   = util::kCurveNeutral;
-};
-
-// The stored sustain-less AHD: wall-clock stage times in SECONDS, Hold as a FRACTION of the
-// span left after them (AhdParams owns why a fraction, not a time).
-struct AhdSeconds {
-    double attackSeconds = 0.0;
-    double decaySeconds  = 0.0;
-    double holdFraction  = 1.0;
-    double attackCurve   = util::kCurveNeutral;
-    double decayCurve    = util::kCurveNeutral;
-};
-
-// The stored AHD pitch envelope. enabled + peakSemitones are dimensionless. The hold fraction
-// defaults to 0 so an instance predating the stage plays as its attack-decay predecessor did.
-struct PitchEnvSeconds {
-    bool       enabled       = false;
-    double     peakSemitones = 0.0;  // signed depth at the peak
-    AhdSeconds shape{0.0, 0.0, /*holdFraction=*/0.0, util::kCurveNeutral, util::kCurveNeutral};
-};
-
-// The stored mirror of the engine's FilterParams (play_params.h, which owns what each field
-// MEANS). Only the envelope differs between the two: the control positions and depths are
-// rate-free already, so this block is a seconds/frames split of one field, not of the whole
-// struct. The env default is a flat unity, so `enabled` is the only thing standing between a
-// loaded blob and the pre-filter sound.
-struct FilterSeconds {
-    bool enabled = false;
-    engine::filter::FilterSettings settings;
-    double modAmount = 0.0;
-    double velAmount = 0.0;
-    double keyTrack  = 0.0;
-    AdsrSeconds env{0.0, 0.0, 0.0, 1.0, 0.0};  // Gate
-    AhdSeconds  trigEnv;                       // Trigger
-    VelocityCurve velocityCurve = VelocityCurve::zero();
-};
-
-// The stored play bundle: wall-clock times in SECONDS, source-timeline quantities in
-// frames/fractions (TriggerParams). Instrument-owned, serialized, editor-facing — distinct
-// from the engine-facing PlayParams (frames).
-struct PlaySeconds {
-    PlayMode        playMode = PlayMode::Gate;
-    AdsrSeconds     adsr;                                 // Gate amp: AHDSR (seconds)
-    TriggerParams   trigger;                              // Trigger play span (%-length)
-    AhdSeconds      trigAhd;                              // Trigger amp: AHD (seconds + fraction)
-    PitchEngine     pitchEngine = kDefaultPitchEngine;    // product default: Preserve
-    PitchEnvSeconds pitchEnv;                             // AHD pitch modulation, off by default
-    VelocityCurve   pitchVelocityCurve = VelocityCurve::zero();  // velocity -> pitch, off by default
-    FilterSeconds   filter;                               // per-voice filter, off by default
-    // The three drawn contours, in the same slots the engine bundle carries them (play_params.h
-    // owns why they sit beside the envelopes rather than inside them). Normalized over the
-    // sample's own length, so resolvePlay needs no rate for them.
-    SplineEnv       ampSpline;
-    SplineEnv       pitchSpline;
-    SplineEnv       filterSpline;
-};
+// --- Seconds -> frames --------------------------------------------------------
 
 // Resolve a stored seconds bundle to the engine's frame-domain PlayParams against a live
 // sample rate (frames = round(seconds * rate)). Source-timeline fields carry through