fix: PTY stdin error, double-click select with full buffer, alt+key passthrough

- Remove proc.stdin.on() call (Bun FileSink has no .on method), add
  try/catch and proc.killed guards to write/resize
- Double-click enters select mode instead of shift+click, with yellow
  banner and Esc-to-exit hint for discoverability
- Select mode now dumps full scrollback buffer (up to 5000 lines) so
  users can scroll up and copy old conversation text
- Pass all Alt+key combos through input parser to PTY (fixes
  Alt+Backspace word deletion and other Alt shortcuts)

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

src/components/direct-grid.ts

@@ -3,7 +3,7 @@
 // Each pane renders independently via PTY capture push callbacks.
 
 import { DirectPane } from "./direct-pane"
-import { startCapture, stopCapture, resizeCapture, resetHash, getLatestFrame, scrollPane, getScrollOffset } from "../pty/capture"
+import { startCapture, stopCapture, resizeCapture, resetHash, getLatestFrame, getFullBuffer, scrollPane, getScrollOffset } from "../pty/capture"
 import { writeToSession, resizeSession, killSession, type PtySession } from "../pty/session-manager"
 import { app, type GridTab } from "../lib/state"
 
@@ -202,17 +202,26 @@ export class DirectGridRenderer {
     const pane = this.focusedPane
     if (!pane) return
     const termW = process.stdout.columns || 120
-    const termH = process.stdout.rows || 40
-    const frame = getLatestFrame(pane.session.name)
-    const lines = frame?.lines ?? []
-
-    let out = SYNC_START + CLEAR
-    // Header: project name + select instructions
+    const lines = getFullBuffer(pane.session.name) ?? []
     const color = getColor(pane.session.colorIndex)
-    out += `\x1b[1;1H${hexFg(color)}${BOLD}${pane.session.projectName}${RESET}  ${DIM}SELECT MODE — drag to select │ cmd+c copy │ Esc exit${RESET}`
-    // Render pane content starting at row 2, column 1 — flush left, no borders
-    for (let r = 0; r < Math.min(lines.length, termH - 2); r++) {
-      out += `\x1b[${r + 2};1H\x1b[${termW}X${lines[r]}\x1b[0m`
+
+    // Banner + all buffer lines dumped as plain text (terminal handles native scrollback)
+    let out = SYNC_START + CLEAR
+
+    // Banner row
+    const bannerBg = hexBg("#e0af68")
+    const bannerFg = "\x1b[38;2;0;0;0m"
+    const bannerText = " SELECTION MODE "
+    const hint = " Esc to exit "
+    const pad = Math.max(0, termW - bannerText.length - hint.length)
+    out += `\x1b[1;1H${bannerBg}${bannerFg}${BOLD}${bannerText}${" ".repeat(pad)}${hint}${RESET}`
+
+    // Project name on row 2
+    out += `\x1b[2;1H${hexFg(color)}${BOLD}${pane.session.projectName}${RESET}  ${DIM}drag to select │ cmd+c copy │ scroll up for history${RESET}`
+
+    // Dump full buffer starting row 3 — native terminal scrollback handles overflow
+    for (let r = 0; r < lines.length; r++) {
+      out += `\x1b[${r + 3};1H${lines[r]}\x1b[0m`
     }
     out += SYNC_END
     this.writeRaw(out)

src/input/handlers.ts

@@ -3,7 +3,7 @@ import { app } from "../lib/state"
 import { updateAll, rebuildDisplayRows, applySortMode, updateTabBar } from "../ui/panels"
 import { extractKeyboardInput, extractMouseEvents } from "./parser"
 import { switchToGrid, switchToGridTab, createNewGridTab } from "../grid/view-switch"
-import { doLaunch } from "../actions/launch"
+import { doLaunch, doAddPane } from "../actions/launch"
 import { launchSelections } from "../actions/launcher"
 import { loadSessions } from "../data/sessions"
 import { loadBranches } from "../data/git"
@@ -338,6 +338,27 @@ export async function handleKeypress(key: KeyEvent) {
     case "g": {
       const row = app.displayRows[app.cursor]
       const project = app.projects[row.projectIndex]
+
+      // Try grid pane navigation first
+      if (app.directGrid && app.gridTabs.length > 0) {
+        const targetSessionId = row.type === "session" && project.sessions
+          ? project.sessions[row.sessionIndex!]?.id
+          : undefined
+
+        for (const tab of app.gridTabs) {
+          const panes = app.directGrid.getTabPanes(tab.id)
+          const paneIdx = targetSessionId
+            ? panes.findIndex(p => p.session.projectPath === project.path && p.session.sessionId === targetSessionId)
+            : panes.findIndex(p => p.session.projectPath === project.path)
+          if (paneIdx >= 0) {
+            switchToGridTab(tab.id)
+            app.directGrid.setFocus(paneIdx)
+            return
+          }
+        }
+      }
+
+      // Fallback: external terminal
       if (project.activeSessions > 0) {
         const sid = row.type === "session" && project.sessions
           ? project.sessions[row.sessionIndex!]?.id
@@ -380,7 +401,18 @@ export async function handleKeypress(key: KeyEvent) {
     case "return": {
       const hasSelections = app.selectedProjects.size > 0 || app.selectedSessions.size > 0
       if (hasSelections) {
-        doLaunch()
+        if (app.addPaneTargetTabId !== null) {
+          doAddPane()
+        } else {
+          doLaunch()
+        }
+        break
+      }
+      if (app.addPaneTargetTabId !== null) {
+        // In add-pane mode with no explicit selections, add cursor item
+        const addRow = app.displayRows[app.cursor]
+        if (addRow) app.selectedProjects.set(app.projects[addRow.projectIndex].path, 1)
+        doAddPane()
         break
       }
       if (app.bottomPanelMode === "idle" && app.cachedIdleSessions.length > 0 && app.idleCursor < app.cachedIdleSessions.length) {
@@ -444,6 +476,16 @@ export async function handleKeypress(key: KeyEvent) {
     }
 
     case "escape":
+      if (app.addPaneTargetTabId !== null) {
+        // Cancel add-pane mode, return to grid
+        const returnTabId = app.addPaneTargetTabId
+        app.addPaneTargetTabId = null
+        app.selectedProjects.clear()
+        app.selectedSessions.clear()
+        app.selectedBranches.clear()
+        switchToGridTab(returnTabId)
+        return
+      }
       if (app.restoreMode === "pending") {
         app.restoreMode = null
         break
@@ -468,7 +510,7 @@ export async function handleKeypress(key: KeyEvent) {
   }
 
   updateAll()
-  } catch {}
+  } catch (err) { console.error("[handleKeypress]", err) }
 }
 
 // ─── Grid input ──────────────────────────────────────────────────────
@@ -521,8 +563,13 @@ export async function handleGridInput(rawSequence: string): Promise<boolean> {
   if (rawSequence === "\x1bn") { handleNextTab(); return true }
   if (rawSequence === "\x1bp") { handlePrevTab(); return true }
 
-  // Ctrl+N / Ctrl+P → focus next/prev pane
-  if (rawSequence === "\x0e") { app.directGrid.focusNext(); return true }
+  // Ctrl+N → add pane to current tab (enter picker in add-pane mode)
+  if (rawSequence === "\x0e") {
+    app.addPaneTargetTabId = app.directGrid.activeTabId
+    switchToPicker()
+    return true
+  }
+  // Ctrl+P → focus prev pane
   if (rawSequence === "\x10") { app.directGrid.focusPrev(); return true }
 
   // Ctrl+F → open folder
@@ -585,6 +632,24 @@ export function switchToPicker() {
   app.renderer.requestRender()
 }
 
+// ─── Double-click detection ──────────────────────────────────────────
+
+let _lastClickTime = 0
+let _lastClickCol = 0
+let _lastClickRow = 0
+const DOUBLE_CLICK_MS = 400
+const DOUBLE_CLICK_DIST = 2
+
+function isDoubleClick(col: number, row: number): boolean {
+  const now = Date.now()
+  const dt = now - _lastClickTime
+  const dist = Math.abs(col - _lastClickCol) + Math.abs(row - _lastClickRow)
+  _lastClickTime = now
+  _lastClickCol = col
+  _lastClickRow = row
+  return dt < DOUBLE_CLICK_MS && dist <= DOUBLE_CLICK_DIST
+}
+
 // ─── Stdin: grid mode ────────────────────────────────────────────────
 
 function processGridInput(str: string) {
@@ -599,9 +664,9 @@ function processGridInput(str: string) {
   for (const me of mouseEvents) {
     if (me.btn === 64) { dg.sendScrollToFocused("up", 3); continue }
     if (me.btn === 65) { dg.sendScrollToFocused("down", 3); continue }
-    // Shift+click (btn bit 2 = shift modifier) → enter select mode for native text selection
-    if ((me.btn & 4) && !me.release) { dg.enterSelectMode(); return }
     if (me.btn === 0 && !me.release) {
+      // Double-click → enter select mode for native text selection
+      if (isDoubleClick(me.col, me.row)) { dg.enterSelectMode(); return }
       const btn = dg.checkButtonClick(me.col, me.row)
       if (btn?.action === "closetab" && btn.tabId !== undefined) {
         const result = dg.requestCloseTab(btn.tabId)

src/input/parser.ts

@@ -65,8 +65,10 @@ export function extractKeyboardInput(data: string): string {
         i += 3; continue
       }
 
-      // Alt+digit (1-9) and Alt+letter (n, p) — keep as keyboard shortcuts
-      if ((next >= "1" && next <= "9") || next === "n" || next === "p") {
+      // Alt+key combos: \x1b + printable/control char — pass through to PTY
+      // Includes Alt+Backspace (\x1b\x7f), Alt+digits, Alt+letters, etc.
+      const nc = data.charCodeAt(i + 1)
+      if ((nc >= 0x20 && nc <= 0x7e) || nc === 0x7f) {
         keyboard += data.slice(i, i + 2)
         i += 2; continue
       }

src/pty/capture.ts

@@ -195,6 +195,14 @@ class VtScreen {
     }
   }
 
+  // Get full buffer: all scrollback lines + current screen (for select mode)
+  getAllLines(): string[] {
+    const lines: string[] = []
+    for (const row of this.scrollback) lines.push(this.renderRow(row))
+    for (let r = 0; r < this.height; r++) lines.push(this.renderRow(this.cells[r]))
+    return lines
+  }
+
   // Get screen as lines with embedded ANSI SGR codes (like tmux capture-pane -e)
   // When scrollOffset > 0, shows scrollback history mixed with screen content
   getLines(): string[] {
@@ -613,6 +621,12 @@ export function getLatestFrame(sessionName: string): CaptureResult | null {
   }
 }
 
+export function getFullBuffer(sessionName: string): string[] | null {
+  const state = panes.get(sessionName)
+  if (!state) return null
+  return state.screen.getAllLines()
+}
+
 export function stopCapture(sessionName: string): void {
   const state = panes.get(sessionName)
   if (!state) return

src/pty/session-manager.ts

@@ -100,18 +100,18 @@ export function killSession(name: string): void {
 
 export function resizeSession(name: string, width: number, height: number): void {
   const session = sessions.get(name)
-  if (!session || !session.alive) return
+  if (!session || !session.alive || session.proc.killed) return
   session.width = width
   session.height = height
   // Send APC resize command: \x1b_R<rows>;<cols>\x1b\\
   const resizeCmd = `\x1b_R${height};${width}\x1b\\`
-  session.proc.stdin.write(resizeCmd)
+  try { session.proc.stdin.write(resizeCmd) } catch {}
 }
 
 export function writeToSession(name: string, data: string): void {
   const session = sessions.get(name)
-  if (!session || !session.alive) return
-  session.proc.stdin.write(data)
+  if (!session || !session.alive || session.proc.killed) return
+  try { session.proc.stdin.write(data) } catch {}
 }
 
 export function isAlive(name: string): boolean {