refactor(tui): statusbar as 4-mode position (on|off|bottom|top)

Default is back to 'on' (inline, above the input) — bottom was too far
from the input and felt disconnected. Users who want it pinned can
opt in explicitly.

- UiState.statusBar: boolean → 'on' | 'off' | 'bottom' | 'top'
- /statusbar [on|off|bottom|top|toggle]; no-arg still binary-toggles
  between off and on (preserves muscle memory)
- appLayout renders StatusRulePane in three slots (inline inside
  ComposerPane for 'on', above transcript row for 'top', after
  ComposerPane for 'bottom'); only the slot matching ui.statusBar
  actually mounts
- drop the input's marginBottom when 'bottom' so the rule sits tight
  against the input instead of floating a row below
- useConfigSync.normalizeStatusBar coerces legacy bool (true→on,
  false→off) and unknown shapes to 'on' for forward-compat reads
- tui_gateway: split compact from statusbar config handlers; persist
  string enum with _coerce_statusbar helper for legacy bool configs

ui-tui/src/app/interfaces.ts

@@ -27,6 +27,8 @@ export interface StateSetter<T> {
   (value: SetStateAction<T>): void
 }
 
+export type StatusBarMode = 'bottom' | 'off' | 'on' | 'top'
+
 export interface SelectionApi {
   clearSelection: () => void
   copySelection: () => string
@@ -89,7 +91,7 @@ export interface UiState {
   showReasoning: boolean
   sid: null | string
   status: string
-  statusBar: boolean
+  statusBar: StatusBarMode
   streaming: boolean
   theme: Theme
   usage: Usage

ui-tui/src/app/slash/commands/core.ts

@@ -8,6 +8,7 @@ import type {
   SessionSteerResponse,
   SessionUndoResponse
 } from '../../../gatewayTypes.js'
+import type { StatusBarMode } from '../../interfaces.js'
 import { writeOsc52Clipboard } from '../../../lib/osc52.js'
 import { configureDetectedTerminalKeybindings, configureTerminalKeybindings } from '../../../lib/terminalSetup.js'
 import type { DetailsMode, Msg, PanelSection } from '../../../types.js'
@@ -305,19 +306,30 @@ export const coreCommands: SlashCommand[] = [
 
   {
     aliases: ['sb'],
-    help: 'toggle status bar',
+    help: 'status bar position (on|off|bottom|top)',
     name: 'statusbar',
     run: (arg, ctx) => {
-      const next = flagFromArg(arg, ctx.ui.statusBar)
+      const mode = arg.trim().toLowerCase()
+      const current = ctx.ui.statusBar
+      // No-arg / `toggle` flips visibility while preserving the last
+      // explicit position: off → on (inline default), any-visible → off.
+      const next: null | StatusBarMode =
+        mode === '' || mode === 'toggle'
+          ? current === 'off'
+            ? 'on'
+            : 'off'
+          : mode === 'on' || mode === 'off' || mode === 'bottom' || mode === 'top'
+            ? mode
+            : null
 
       if (next === null) {
-        return ctx.transcript.sys('usage: /statusbar [on|off|toggle]')
+        return ctx.transcript.sys('usage: /statusbar [on|off|bottom|top|toggle]')
       }
 
       patchUiState({ statusBar: next })
-      ctx.gateway.rpc<ConfigSetResponse>('config.set', { key: 'statusbar', value: next ? 'on' : 'off' }).catch(() => {})
+      ctx.gateway.rpc<ConfigSetResponse>('config.set', { key: 'statusbar', value: next }).catch(() => {})
 
-      queueMicrotask(() => ctx.transcript.sys(`status bar ${next ? 'on' : 'off'}`))
+      queueMicrotask(() => ctx.transcript.sys(`status bar ${next}`))
     }
   },
 

ui-tui/src/app/uiStore.ts

@@ -16,7 +16,7 @@ const buildUiState = (): UiState => ({
   showReasoning: false,
   sid: null,
   status: 'summoning hermes…',
-  statusBar: true,
+  statusBar: 'on',
   streaming: true,
   theme: DEFAULT_THEME,
   usage: ZERO

ui-tui/src/app/useConfigSync.ts

@@ -10,9 +10,23 @@ import type {
 } from '../gatewayTypes.js'
 import { asRpcResult } from '../lib/rpc.js'
 
+import type { StatusBarMode } from './interfaces.js'
 import { turnController } from './turnController.js'
 import { patchUiState } from './uiStore.js'
 
+const STATUSBAR_MODES = new Set<StatusBarMode>(['bottom', 'off', 'on', 'top'])
+
+// Legacy configs stored tui_statusbar as a bool; new configs write a string
+// ('on' | 'off' | 'bottom' | 'top'). Coerce both shapes so existing users
+// keep their preference without manual migration.
+export const normalizeStatusBar = (raw: unknown): StatusBarMode => {
+  if (raw === false) return 'off'
+  if (raw === true || raw == null) return 'on'
+  if (typeof raw === 'string' && STATUSBAR_MODES.has(raw as StatusBarMode)) return raw as StatusBarMode
+
+  return 'on'
+}
+
 const MTIME_POLL_MS = 5000
 
 const quietRpc = async <T extends Record<string, any> = Record<string, any>>(
@@ -37,7 +51,7 @@ export const applyDisplay = (cfg: ConfigFullResponse | null, setBell: (v: boolea
     inlineDiffs: d.inline_diffs !== false,
     showCost: !!d.show_cost,
     showReasoning: !!d.show_reasoning,
-    statusBar: d.tui_statusbar !== false,
+    statusBar: normalizeStatusBar(d.tui_statusbar),
     streaming: d.streaming !== false
   })
 }