add vscode tmux instructions

.vscode/vscode.md

@@ -21,11 +21,23 @@ Add to user keyboard settings (json)
 
 ## Shell
 
-Edit settings.json
+I would recommend using tmux as your default shell. VSCode automatically creates new
+sessions when adding or splitting windows. The only small problem is closing out of
+vscode and reopening it won't reattach the previous sessions. You'll need to run
+`tmux switch-client -t #` to get back to each session you lost.
 
 ```json
+"terminal.integrated.profiles.osx": {
+  //...existing profiles...
+  "tmux-shell": {
+    "path": "tmux",
+  }
+}
+```
+
+```bash
 {
-    "terminal.integrated.defaultProfile.linux": "zsh",
+    "terminal.integrated.defaultProfile.linux": "tmux",
 }
 ```