chore(tui): /clean recent perf work — KISS/DRY pass

24 files, -319 LoC. Behaviour preserved, 369/369 tests green.

- hermes-ink caches: shared lruEvict helper for the four parallel LRU
  caches (stringWidth, wrapText, sliceAnsi, lineWidth); touch-on-read
  stays inlined per cache; tightened output.ts skip-slice fast path.
- wheelAccel: trimmed provenance header, collapsed env parsing, ternary
  dispatch in computeWheelStep.
- perfPane: folded ensureLogDir into once-flag, spread-with-overrides
  for fastPath/phases instead of full rebuilds.
- env: extracted truthy() (used 4×).
- virtualHeights: collapsed user/diff/slash height bumps; trail+todos
  estimate.
- useInputHandlers: scrollIdleTimer cleanup on unmount, ?? undefined
  shorthand.
- useMainApp: dropped dead liveTailVisible IIFE and liveProgress
  indirection.
- appLayout, markdown, messageLine, entry: vertical rhythm, dropped
  narration comments, inlined one-shot vars.
- fix: empty catch blocks → /* best-effort */ for no-empty lint.

ui-tui/src/lib/text.ts

@@ -80,21 +80,16 @@ export const pasteTokenLabel = (text: string, lineCount: number) => {
 const THINKING_STATUS_RE = new RegExp(`^(?:${VERBS.join('|')})\\.{0,3}$`, 'i')
 const THINKING_STATUS_CHUNK_RE = new RegExp(`[^A-Za-z\n]+\\s*(?:${VERBS.join('|')})\\.{0,3}\\s*`, 'giu')
 
-const normalizeThinkingParagraphs = (text: string) =>
-  text
+export const cleanThinkingText = (reasoning: string) =>
+  reasoning
+    .split('\n')
+    .map(line => line.replace(THINKING_STATUS_CHUNK_RE, '').trim())
+    .filter(line => line && !THINKING_STATUS_RE.test(line.replace(/\.\.\.$/, '').trim()))
+    .join('\n')
     .replace(/([^\n])(?=\*\*[^*\n][^\n]*?\*\*)/g, '$1\n\n')
     .replace(/\n{3,}/g, '\n\n')
     .trim()
 
-export const cleanThinkingText = (reasoning: string) =>
-  normalizeThinkingParagraphs(
-    reasoning
-      .split('\n')
-      .map(line => line.replace(THINKING_STATUS_CHUNK_RE, '').trim())
-      .filter(line => line && !THINKING_STATUS_RE.test(line.replace(/\.\.\.$/, '').trim()))
-      .join('\n')
-  )
-
 export const thinkingPreview = (reasoning: string, mode: ThinkingMode, max: number = THINKING_COT_MAX) => {
   const raw = cleanThinkingText(reasoning)