fix: clear terminal on connect, increase SIGWINCH settle time to 600ms

Sources/UI/Terminal/MainTerminalView.swift

@@ -103,20 +103,27 @@ struct MainTerminalView: View {
                 Task { try? await conn.send(.keys(data: text)) }
             }
 
-            // On first connection: resize → brief pause (SIGWINCH propagation)
+            // On first connection:
-            // → snapshot. This avoids replaying history at the wrong size.
+            //   1. Clear SwiftTerm immediately (removes stale content)
+            //   2. Send resize so tmux + shell know the real dimensions
+            //   3. Wait for SIGWINCH to propagate and shell to redraw
+            //   4. Snapshot the now-stable screen state
             conn.$connectionState
                 .filter { $0 == .connected }
                 .first()
                 .receive(on: DispatchQueue.main)
                 .sink { [weak conn, terminalVC] _ in
+                    // Clear immediately — don’t show stale/mismatched content.
+                    terminalVC.feed(data: Data("\u{1B}[H\u{1B}[2J".utf8))
+
                     Task { @MainActor in
                         let (cols, rows) = terminalVC.terminalSize
                         if cols > 0 && rows > 0 {
                             try? await conn?.send(.resize(cols: cols, rows: rows))
                         }
-                        // Let tmux propagate SIGWINCH before snapshotting.
+                        // 600 ms: SIGWINCH → fish/bash redraws → tmux pane settles.
-                        try? await Task.sleep(nanoseconds: 250_000_000)
+                        // SSH sessions need extra round-trip time.
+                        try? await Task.sleep(nanoseconds: 600_000_000)
                         try? await conn?.send(.snapshotRequest)
                     }
                 }