fix(examples): copy /etc/skel on init in docker template (#12913)

Fixes #10209

examples/templates/docker/main.tf

@@ -28,6 +28,12 @@ resource "coder_agent" "main" {
   startup_script = <<-EOT
     set -e
 
+    # Prepare user home with default files on first start.
+    if [ ! -f ~/.init_done ]; then
+      cp -rT /etc/skel ~
+      touch ~/.init_done
+    fi
+
     # install and start code-server
     curl -fsSL https://code-server.dev/install.sh | sh -s -- --method=standalone --prefix=/tmp/code-server --version 4.19.1
     /tmp/code-server/bin/code-server --auth none --port 13337 >/tmp/code-server.log 2>&1 &