feat: tmux 动态 resize（iPadOS 拖拽窗口/旋转自适应）

- ContentView 观测 onChange(geo.size)/onAppear → controller.containerResized
- containerResized: 点尺寸 × displayScale ÷ cell 像素 = 目标 cols×rows，去重 + debounce(200ms)
  → refresh-client -C WxH → tmux 重排回 %layout-change → 更新 pane frame
- cell 像素来自 raw 终端/pane surface metrics(InMemoryTerminalViewport.cellWidthPixels)；
  surface resize 回调只 noteCellPixels 不驱动 tmux（防反馈环，单向数据流）
- 验证：容器 1032x1280@2x cell16x35→129x73，tmux 根 rect 精确采纳，2 pane 复用不重建

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/TerminalX/iOS/TmuxController.swift

@@ -14,12 +14,15 @@ final class TmuxPaneSurface: ObservableObject, Identifiable {
     /// 初始 `capture-pane` 应答到达前丢弃该 pane 的 %output（避免与快照重复）；tmux 单线程串行保证正确。
     var awaitingCapture = true
 
-    init(id: TmuxPaneID, cols: Int, rows: Int, onInput: @escaping @Sendable (Data) -> Void) {
+    init(id: TmuxPaneID, cols: Int, rows: Int,
+         onInput: @escaping @Sendable (Data) -> Void,
+         onMetrics: @escaping @Sendable (Int, Int) -> Void) {
         self.id = id
         self.grid = (cols, rows)
         let session = InMemoryTerminalSession(
             write: { data in onInput(data) },   // 输入直接绑到本 pane → send-keys -t %self
-            resize: { _ in }                     // tmux 模式：surface resize 不反向驱动 tmux（防反馈环）
+            // tmux 模式：surface resize 只回报 cell 像素供换算，绝不反向驱动 tmux（防反馈环）。
+            resize: { vp in onMetrics(Int(vp.cellWidthPixels), Int(vp.cellHeightPixels)) }
         )
         let state = TerminalViewState()
         state.configuration = TerminalSurfaceOptions(backend: .inMemory(session))
@@ -60,6 +63,9 @@ final class TmuxController: ObservableObject {
     var onExit: (() -> Void)?
 
     private var clientCols = 80, clientRows = 24
+    private var cellWpx = 0, cellHpx = 0       // cell 设备像素（换算容器点尺寸→格子）
+    private var lastSentCols = 0, lastSentRows = 0
+    private var resizeDebounce: Task<Void, Never>?
 
     // control-mode 命令应答 FIFO 匹配。
     private var attachAcked = false
@@ -73,6 +79,30 @@ final class TmuxController: ObservableObject {
     /// 由 model 在 attach 前告知全屏格子（tmux 据此 refresh-client -C 布局）。
     func setClientSize(cols: Int, rows: Int) { clientCols = max(1, cols); clientRows = max(1, rows) }
 
+    /// cell 设备像素（来自 raw 终端或 pane surface metrics）。
+    func setCellPixels(w: Int, h: Int) { if w > 0 { cellWpx = w }; if h > 0 { cellHpx = h } }
+    /// pane surface metrics 回报（仅刷新 cell 缓存，绝不反向驱动 tmux）。
+    func noteCellPixels(w: Int, h: Int) { setCellPixels(w: w, h: h) }
+
+    /// 容器尺寸变化（iPadOS 拖拽窗口/旋转/分屏）：换算总格子 → 去重 + debounce → refresh-client -C。
+    /// 单向数据流：尺寸只来自"容器点尺寸 × displayScale ÷ cell 像素"，绝不来自 surface resize 回调（防反馈环）。
+    func containerResized(widthPt: CGFloat, heightPt: CGFloat, scale: CGFloat) {
+        guard cellWpx > 0, cellHpx > 0, widthPt > 0, heightPt > 0, scale > 0 else { return }
+        let cols = max(1, Int(widthPt * scale / CGFloat(cellWpx)))
+        let rows = max(1, Int(heightPt * scale / CGFloat(cellHpx)))
+        guard cols != lastSentCols || rows != lastSentRows else { return }
+        lastSentCols = cols; lastSentRows = rows
+        clientCols = cols; clientRows = rows
+        NSLog("TMUXDBG containerResized pt=\(Int(widthPt))x\(Int(heightPt)) scale=\(scale) cell=\(cellWpx)x\(cellHpx) -> \(cols)x\(rows)")
+        resizeDebounce?.cancel()
+        resizeDebounce = Task { [weak self] in
+            try? await Task.sleep(nanoseconds: 200_000_000)   // 合并拖拽期间的连续变化
+            guard !Task.isCancelled, let self, self.attachAcked else { return }
+            NSLog("TMUXDBG refresh-client -C \(cols)x\(rows)")
+            self.sendCommand("refresh-client -C \(cols)x\(rows)")   // tmux 重排 → 回 %layout-change → 更新 frame
+        }
+    }
+
     var activeWindow: TmuxWindow? {
         guard let id = activeWindowID else { return windows.first }
         return windowByID[id]
@@ -139,6 +169,8 @@ final class TmuxController: ObservableObject {
         }
         win.fullLayout = fullTree
         win.visibleLayout = visTree   // 单次发布 → SwiftUI 单帧更新，无闪烁
+        let rr = fullTree.root.rect
+        NSLog("TMUXDBG layout win=@\(w.raw) root=\(rr.width)x\(rr.height) panes=\(fullTree.paneIDs.count)")
         if win.activePane == nil || !newPanes.contains(win.activePane!) {
             win.activePane = fullTree.paneIDs.first
         }
@@ -155,9 +187,11 @@ final class TmuxController: ObservableObject {
         paneToWindow[p] = w
         guard let win = windowByID[w] else { return }
         if let existing = surfaceByPane[p] { existing.grid = (cols, rows); return }  // 复用，不重建
-        let surface = TmuxPaneSurface(id: p, cols: cols, rows: rows) { [weak self] data in
-            self?.sendKeys(pane: p, data: data)
-        }
+        let surface = TmuxPaneSurface(
+            id: p, cols: cols, rows: rows,
+            onInput: { [weak self] data in self?.sendKeys(pane: p, data: data) },
+            onMetrics: { [weak self] w, h in Task { @MainActor in self?.noteCellPixels(w: w, h: h) } }
+        )
         surfaceByPane[p] = surface
         win.panes[p] = surface
         // 抓初始屏（capture %end 后放行 %output）。