An editable AHDSR amplitude envelope on the SampleView's seconds axis (or any positioned box). Attack, hold, decay-and-sustain and release nodes drag and step as sliders; the sustain plateau drags vertically. Every value goes through the stage descriptor's taper, range and step exactly like the knob path (knob-core curves, pinned equal to audio-contracts normalize/denormalize), and arrow keys are the knob's keys. Segments past the take end are drawn dimmed; note-off is drawn at a host gate. Pure geometry exported and tested.
pnpm dlx shadcn@latest add "https://pluginui.com/r/core-envelope-overlay.json"