fix(ui): deliver AltGr characters to ConPTY tiles as text

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

docs/explore-notes/conpty-sessions.md

@@ -327,6 +327,8 @@ bails out immediately instead of racing past the collection-based dedupe.
 (scoped to `MainWindow` via `AddClassHandler<MainWindow>`) never runs there — **Escape always
 reaches the PTY**. See the note in `src/ClaudeDo.Ui/CLAUDE.md`.
 
+**AltGr bypass:** Windows reports AltGr as Ctrl+Alt, and Iciclecreek's `TerminalView.OnKeyDown` turns any Ctrl/Alt combo into a control sequence (NUL/0x1C/ESC) and marks it handled, so `@ \ { } € ~ |` never arrive as text. `InteractiveTerminalView.OnPreviewKeyDown` (tunnel) detects it via `IsAltGrText` and sends `KeySymbol` through `SendTextAsync` first.
+
 `TaskRowViewModel.HasInteractiveSession` shows an accent "Interactive" chip instead of "Parked";
 tapping it jumps to that Mission Control pane. `TasksIslandViewModel.SyncInteractiveSessions`
 mirrors Mission Control's open panes onto the rows.

src/ClaudeDo.Ui/Views/InteractiveTerminalView.axaml.cs

@@ -40,6 +40,15 @@ public partial class InteractiveTerminalView : UserControl
 
     private void OnPreviewKeyDown(object? sender, KeyEventArgs e)
     {
+        // AltGr arrives as Ctrl+Alt; the library would turn it into a control sequence (and mark it handled).
+        if (IsAltGrText(e.KeyModifiers, e.KeySymbol))
+        {
+            if (DataContext is not InteractiveTerminalViewModel altGrVm) return;
+            e.Handled = true;
+            _ = SendTextAndReportAsync(altGrVm, e.KeySymbol!);
+            return;
+        }
+
         if (e.Key != Key.V || !e.KeyModifiers.HasFlag(KeyModifiers.Control) || e.KeyModifiers.HasFlag(KeyModifiers.Alt))
             return;
         if (DataContext is not InteractiveTerminalViewModel vm) return;
@@ -120,6 +129,12 @@ public partial class InteractiveTerminalView : UserControl
             vm.ReportSendFailed();
     }
 
+    /// <summary>True for an AltGr keystroke (Windows reports it as Ctrl+Alt) whose
+    /// <paramref name="keySymbol"/> is already a single printable character, e.g. "@" or "\".</summary>
+    internal static bool IsAltGrText(KeyModifiers modifiers, string? keySymbol) =>
+        modifiers.HasFlag(KeyModifiers.Control) && modifiers.HasFlag(KeyModifiers.Alt)
+        && keySymbol is { Length: 1 } && !char.IsControl(keySymbol[0]);
+
     /// <summary>Joins dropped file paths into one insertable chunk: quoted when they contain a
     /// space, space-separated, with a trailing space so the user can keep typing.</summary>
     internal static string FormatDroppedPaths(IEnumerable<string?>? paths)

tests/ClaudeDo.Ui.Tests/Views/InteractiveTerminalDropPathsTests.cs

@@ -1,3 +1,4 @@
+using Avalonia.Input;
 using ClaudeDo.Ui.Views;
 using Xunit;
 
@@ -23,4 +24,18 @@ public class InteractiveTerminalDropPathsTests
         Assert.Equal(string.Empty, InteractiveTerminalView.FormatDroppedPaths(new string?[] { null }));
         Assert.Equal(string.Empty, InteractiveTerminalView.FormatDroppedPaths(null));
     }
+
+    [Theory]
+    [InlineData(KeyModifiers.Control | KeyModifiers.Alt, "@", true)]
+    [InlineData(KeyModifiers.Control | KeyModifiers.Alt, "\\", true)]
+    [InlineData(KeyModifiers.Control, "c", false)]
+    [InlineData(KeyModifiers.Alt, "@", false)]
+    [InlineData(KeyModifiers.None, "@", false)]
+    [InlineData(KeyModifiers.Control | KeyModifiers.Alt, "\u0003", false)]
+    [InlineData(KeyModifiers.Control | KeyModifiers.Alt, "", false)]
+    [InlineData(KeyModifiers.Control | KeyModifiers.Alt, null, false)]
+    public void IsAltGrText_only_for_ctrl_alt_with_one_printable_char(KeyModifiers modifiers, string? symbol, bool expected)
+    {
+        Assert.Equal(expected, InteractiveTerminalView.IsAltGrText(modifiers, symbol));
+    }
 }