[LeeO86]

Promotion dev → stage for a FlowXer release (Adrian OK'd stage and main on 2026-10-23).

• T-bar as a real lever (ping-pong), flicker fixed, T-bar widget #113: the T-bar is a real lever (ping-pong). The handle stays at the end a transition took it to; the next transition is made by moving it back (bottom → top, then down again). The mixer keeps where the lever rests (tbar_end per ME, saved; it flips with each transition the T-bar or an Auto completes, and with a Cut of a held one), so every console, the widget and a hardware panel agree.
  • Flicker fixed: the drag follows only the pointer (from where the handle was grabbed; a click on the track does nothing), sends one position at a time and in order (newest wins), is latched at the end until release, starts nothing within 2 % of the resting end and snaps within 2 % of either end while held; the browser can no longer cancel the drag with a text drag. With a stinger or BKGD off one drag fires one Auto. A drag from an end another console's Auto or Cut has changed is ignored (no take back).
  • Hardware levers: a lever without from counts only after it has come to the resting end (pickup) — at start, after an engine restart or a loaded state, and after each change of the end; several hardware levers are told apart by the optional source.
  • New widget /widget/tbar[?me=<n>][&buttons=false]: the ME's lever with Cut and Auto.
  • API additions, backward compatible: POST /mixer/position takes lever (0 top … 1 bottom) with optional from (top/bottom) and source instead of position (which keeps its meaning); an ignored lever value answers 200 {status: "ignored", reason: "stale_from" | "pickup"}; GET /console has tbar per ME (end, position, lever); panels have tbar_end. position: 1 straight from rest now completes the transition (it answered 500).

Tested in the lab only: pytest and GUI check scripts (drags that complete, reverse drags, deadband, pickup, stale from, the send queue), and headless Chrome drags in simulate mode (console and widget, another console's Auto during a drag). No platform test image.

Version, platform contract and upgrade notes: CHANGELOG.md.

🤖 Generated with Claude Code

https://claude.ai/code/session_01St7QwmonpoG9EEEqaLFXLi