visual-cadencelisted

# visual-cadence Static-gap measurement. Runs in the finishing phase right AFTER `qc-clip` passes, on the final clip. It is the union-of-all-visual-changes counterpart to the per-skill cut planners — `jump-cut`, `zoom-punch`, and b-roll each place cuts blind to one another, so only a post-render measure tells you what a viewer actually sees. It is the keystone signal for the "12 seconds without a pattern interrupt" retention leak diagnosed on the channel. ``` visual-cadence.sh <clip.mp4> [out.json=<clip>.cadence.json] [max_gap=5.0] ``` - **How.** `ffmpeg ... -vf select='gt(scene,VCAD_SCENE)',showinfo` flags frames whose scene-change score exceeds the threshold; the script parses their `pts_time`, treats `[0, ...cuts..., dur]` as boundaries, and reports the largest gap. Hard cuts (b-roll) and strong reframes (jump-cut) register; gradual zoom-punch pulses intentionally do not count as a "change." - **Output.** `{pass, duration, threshold, scene, n_changes, max_gap, gap_window:[a,b], changes:[...]}`. - **Diagnostic only.** Always exits 0 (usage/missing-input aside); it writes the verdict and logs a `WARN` when `max_gap > MAX_STATIC_GAP`, but never blocks the save. The real fix lives upstream in `jump-cut` coverage; this surfaces regressions. - **Idempotent** via `.vcadmeta`. `VISUAL_CADENCE=0` disables. Knobs: `VISUAL_CADENCE` (0 disables), `MAX_STATIC_GAP` (default 5.0s), `VCAD_SCENE` (scene-detect threshold, default 0.3).