docs(plans): record why the de-esser and tone match were not built

De-esser is deferred with its two design constraints written down, because
neither is visible until you try to build it: analyseCarveDynamics' 85-150 ms
hop cannot land on 50-150 ms sibilants and needs re-parameterising, and
MAX_AUTOMATION_POINTS is 512 while a long voiceover holds hundreds of sibilant
events at three or four points each — so a naive lane blows the cap and the
scheduler truncates it silently, leaving an envelope that stops partway through
the clip. The leveller is its structural template.

Tone match is superseded for v1. It existed to let a casual author fix a
track's tone without understanding frequencies, and the Tone EQ now does that
with a control they already know and does it predictably. What is left is
matching one track to another, which is genuinely advanced and carries real
unknowns nobody has asked us to resolve.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: vanceingalls

plans/audio-fx-presets.md

@@ -454,6 +454,33 @@ also dissolved the duplicate-name problem at the root.
 it to an absolute figure turns levelling into a volume change. The 80th
 percentile of the track's own speaking windows is the figure that works.
 
+## 6c. The two scripts NOT built, and why
+
+**De-esser — deferred, not abandoned.** The leveller is its structural template:
+analysis → profile → result → remove → summary, with a mutation pass over each.
+Two constraints have to be designed for before it is written, and neither is
+visible until you try:
+
+1. `analyseCarveDynamics` cannot be reused unchanged. Its hop is
+   `max(FRAME, length / POINT_BUDGET)` — 85 ms at best, ~150 ms on a
+   real-length track — while sibilants are 50–150 ms events. At that resolution
+   the envelope cannot land on them, and its `ATTACK_S`/`RELEASE_S` are tuned
+   for musical ducking besides. Same machinery, re-parameterised for a
+   sibilance timescale.
+2. **`MAX_AUTOMATION_POINTS` is 512.** A dip needs three or four points, and a
+   long voiceover holds hundreds of sibilant events, so a naive lane blows the
+   cap and the scheduler truncates it — silently, leaving an envelope that
+   stops partway through the clip. Budget it up front: strongest-N events, or
+   merge adjacent dips.
+
+**Tone match — superseded for v1.** It existed to give a casual author a way to
+fix the tone of a track without understanding frequencies. The Tone EQ now does
+that with a control they already know, and it does it *predictably*, which
+matching against a reference clip does not. What remains is genuinely advanced
+— matching one track to another — and it carries real unknowns: which reference,
+how much correction, what to do when the two sources have different content.
+Not worth building before anyone has asked for it.
+
 ## 7. What to build first
 
 1. **Character presets** (§5c) — highest ratio of delight to risk. Pure