refactor(tui): store-driven turn state + slash registry + module split

Hoist turn state from a 286-line hook into $turnState atom + turnController
singleton. createGatewayEventHandler becomes a typed dispatch over the
controller; its ctx shrinks from 30 fields to 5. Event-handler refs and 16
threaded actions are gone.

Fold three createSlash*Handler factories into a data-driven SlashCommand[]
registry under slash/commands/{core,session,ops}.ts. Aliases are data;
findSlashCommand does name+alias lookup. Shared guarded/guardedErr combinator
in slash/guarded.ts.

Split constants.ts + app/helpers.ts into config/ (timing/limits/env),
content/ (faces/placeholders/hotkeys/verbs/charms/fortunes), domain/ (roles/
details/messages/paths/slash/viewport/usage), protocol/ (interpolation/paste).

Type every RPC response in gatewayTypes.ts (26 new interfaces); drop all
`(r: any)` across slash + main app.

Shrink useMainApp from 1216 -> 646 lines by extracting useSessionLifecycle,
useSubmission, useConfigSync. Add <Fg> themed primitive and strip ~50
`as any` color casts.

Tests: 50 passing. Build + type-check clean.

ui-tui/src/content/charms.ts

@@ -0,0 +1 @@
+export const LONG_RUN_CHARMS = ['still cooking…', 'polishing edges…', 'asking the void nicely…']

ui-tui/src/content/faces.ts

@@ -0,0 +1,17 @@
+export const FACES = [
+  '(｡•́︿•̀｡)',
+  '(◔_◔)',
+  '(¬‿¬)',
+  '( •_•)>⌐■-■',
+  '(⌐■_■)',
+  '(´･_･`)',
+  '◉_◉',
+  '(°ロ°)',
+  '( ˘⌣˘)♡',
+  'ヽ(>∀<☆)☆',
+  '٩(๑❛ᴗ❛๑)۶',
+  '(⊙_⊙)',
+  '(¬_¬)',
+  '( ͡° ͜ʖ ͡°)',
+  'ಠ_ಠ'
+]

ui-tui/src/content/fortunes.ts

@@ -0,0 +1,40 @@
+const FORTUNES = [
+  'you are one clean refactor away from clarity',
+  'a tiny rename today prevents a huge bug tomorrow',
+  'your next commit message will be immaculate',
+  'the edge case you are ignoring is already solved in your head',
+  'minimal diff, maximal calm',
+  'today favors bold deletions over new abstractions',
+  'the right helper is already in your codebase',
+  'you will ship before overthinking catches up',
+  'tests are about to save your future self',
+  'your instincts are correctly suspicious of that one branch'
+]
+
+const LEGENDARY_FORTUNES = [
+  'legendary drop: one-line fix, first try',
+  'legendary drop: every flaky test passes cleanly',
+  'legendary drop: your diff teaches by itself'
+]
+
+const hash = (input: string) => {
+  let out = 2166136261
+
+  for (let i = 0; i < input.length; i++) {
+    out ^= input.charCodeAt(i)
+    out = Math.imul(out, 16777619)
+  }
+
+  return out >>> 0
+}
+
+const fromScore = (score: number) => {
+  const rare = score % 20 === 0
+  const bag = rare ? LEGENDARY_FORTUNES : FORTUNES
+
+  return `${rare ? '🌟' : '🔮'} ${bag[score % bag.length]}`
+}
+
+export const randomFortune = () => fromScore(Math.floor(Math.random() * 0x7fffffff))
+
+export const dailyFortune = (seed: null | string) => fromScore(hash(`${seed || 'anon'}|${new Date().toDateString()}`))

ui-tui/src/content/hotkeys.ts

@@ -0,0 +1,19 @@
+export const HOTKEYS: [string, string][] = [
+  ['Ctrl+C', 'interrupt / clear draft / exit'],
+  ['Ctrl+D', 'exit'],
+  ['Ctrl+G', 'open $EDITOR for prompt'],
+  ['Ctrl+L', 'new session (clear)'],
+  ['Alt+V / /paste', 'paste clipboard image'],
+  ['Tab', 'apply completion'],
+  ['↑/↓', 'completions / queue edit / history'],
+  ['Ctrl+A/E', 'home / end of line'],
+  ['Ctrl+Z / Ctrl+Y', 'undo / redo input edits'],
+  ['Ctrl+W', 'delete word'],
+  ['Ctrl+U/K', 'delete to start / end'],
+  ['Ctrl+←/→', 'jump word'],
+  ['Home/End', 'start / end of line'],
+  ['Shift+Enter / Alt+Enter', 'insert newline'],
+  ['\\+Enter', 'multi-line continuation (fallback)'],
+  ['!cmd', 'run shell command'],
+  ['{!cmd}', 'interpolate shell output inline']
+]

ui-tui/src/content/placeholders.ts

@@ -0,0 +1,13 @@
+import { pick } from '../lib/text.js'
+
+export const PLACEHOLDERS = [
+  'Ask me anything…',
+  'Try "explain this codebase"',
+  'Try "write a test for…"',
+  'Try "refactor the auth module"',
+  'Try "/help" for commands',
+  'Try "fix the lint errors"',
+  'Try "how does the config loader work?"'
+]
+
+export const PLACEHOLDER = pick(PLACEHOLDERS)

ui-tui/src/content/verbs.ts

@@ -0,0 +1,38 @@
+export const TOOL_VERBS: Record<string, string> = {
+  browser: 'browsing',
+  clarify: 'asking',
+  create_file: 'creating',
+  delegate_task: 'delegating',
+  delete_file: 'deleting',
+  execute_code: 'executing',
+  image_generate: 'generating',
+  list_files: 'listing',
+  memory: 'remembering',
+  patch: 'patching',
+  read_file: 'reading',
+  run_command: 'running',
+  search_code: 'searching',
+  search_files: 'searching',
+  terminal: 'terminal',
+  web_extract: 'extracting',
+  web_search: 'searching',
+  write_file: 'writing'
+}
+
+export const VERBS = [
+  'pondering',
+  'contemplating',
+  'musing',
+  'cogitating',
+  'ruminating',
+  'deliberating',
+  'mulling',
+  'reflecting',
+  'processing',
+  'reasoning',
+  'analyzing',
+  'computing',
+  'synthesizing',
+  'formulating',
+  'brainstorming'
+]