Phase 5: voice consistency pass

Tier-1 voice-consistency pass: whole-document LLM review surfacing passages
that read tonally out of place (formal/over-polished/paraphrased-too-closely),
as honey-decorated `voice` flags with no correction (awareness-only).

- internal/llm/voice.go: RunVoice sends the whole document (no TruncateDoc),
  MaxTokens 2048, 20s per-doc floor (VoiceInterval). Standalone voice prompt
  in prompts.go (not bundled with the grammar checkpoint, per spec).
- internal/suggestions: POST /api/docs/:id/voice. replacePending is now
  family-scoped (pendingScope) so grammar and voice never clobber each other's
  pending flags; both passes return the unified pending set. check/voice share
  one runPass helper. TestVoicePassCoexists covers both directions.
- Frontend: api.voiceDoc, useCheckpoint voicing/runVoice, honey "Check my
  voice" toolbar pill, breathing honey dot in StatusBar.

Claude-Session: https://claude.ai/code/session_016Yr6jELuRc7hyzYLccQKZd

web/src/components/Toolbar/Toolbar.tsx

@@ -3,6 +3,9 @@ import { useEditorState } from '@tiptap/react'
 
 interface Props {
   editor: Editor | null
+  // Runs the whole-document voice-consistency pass; `voicing` shows its progress.
+  onVoiceCheck: () => void
+  voicing: boolean
 }
 
 // A formatting button. `active` gets the rose pill treatment so the writer can
@@ -47,7 +50,7 @@ const Divider = () => (
 // Toolbar renders inline formatting controls bound to the live Tiptap editor.
 // useEditorState subscribes to just the flags it reads, so the buttons reflect
 // the current selection without re-rendering the whole tree on every keystroke.
-export function Toolbar({ editor }: Props) {
+export function Toolbar({ editor, onVoiceCheck, voicing }: Props) {
   const state = useEditorState({
     editor,
     selector: ({ editor }) =>
@@ -134,6 +137,28 @@ export function Toolbar({ editor }: Props) {
       >
         ⇥
       </TBtn>
+      <Divider />
+      <button
+        type="button"
+        aria-label="Check my voice"
+        disabled={voicing}
+        onMouseDown={(e) => e.preventDefault()} // keep editor selection
+        onClick={onVoiceCheck}
+        className="ml-0.5 inline-flex h-8 items-center gap-1.5 whitespace-nowrap px-3 text-xs font-bold transition-colors disabled:opacity-70"
+        style={{
+          borderRadius: 'var(--radius-pill)',
+          color: 'var(--color-plum)',
+          background: 'var(--color-honey)',
+        }}
+        title="Read the whole document for passages that don't sound like you"
+      >
+        <span
+          className={voicing ? 'petal-checkpoint-dot inline-block h-2 w-2 rounded-full' : 'hidden'}
+          style={{ background: 'var(--color-plum)' }}
+          aria-hidden
+        />
+        {voicing ? 'Reading…' : 'Check my voice 🍯'}
+      </button>
     </div>
   )
 }