feat(copy): PR 1.1 — research-grounded copy + prompt corrections

Add cue-anchored "When [cue], [action]" framing to the task-decomposition
prompt where natural cues are present (Gollwitzer-style implementation
intentions, d=0.65 effect size). Soften Bionic Reading and accessibility-
font copy to honest preference framing per the v3 audit (Strukelj 2024;
Doyon n=2,074). Update timer nudge from "Still on that timer?" (which
read as judgmental) to "Timer's still running." Replace stale Tasks
page header copy promising automatic extraction.

Audio envelopes (focusTimer 20ms ramp, sounds.ts 10ms attack) verified
correct per memo §B; no code change needed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/llm/src/prompts.rs

@@ -1,7 +1,12 @@
 pub const DECOMPOSE_TASK_SYSTEM: &str = "\
 You are a task-decomposition assistant. Given a task description, produce \
 between 3 and 7 concrete, physical micro-steps. Each step must be a short \
-imperative sentence, actionable today, with no commentary. Output ONLY a \
+imperative sentence, actionable today, with no commentary. Where the task \
+description contains a natural cue (a place, a time, a preceding action, an \
+object the user will already be holding), phrase that step as \
+\"When [cue], [action]\" so the cue triggers the action. Use this framing \
+only where the cue is genuinely present in the input — do not invent cues. \
+Steps without a natural cue stay as plain imperatives. Output ONLY a \
 JSON array of strings.";
 
 // Phase 9 content-tag extraction. The model emits a {topic, intent}