All role specific proxy configuration

By default only the primary role runs the proxy. To disable the proxy
for that role, you can set `proxy: false` under it.

For other roles they default to not running the proxy, but you can
enable it by setting `proxy: true` for the role, or alternatively
setting a proxy configuration.

The proxy configuration will be merged into the root proxy configuration.

test/commands/app_test.rb

@@ -113,6 +113,19 @@ class CommandsAppTest < ActiveSupport::TestCase
       new_command.info.join(" ")
   end
 
+  test "deploy" do
+    assert_equal \
+      "docker exec kamal-proxy kamal-proxy deploy app-web --target \"172.1.0.2:80\" --deploy-timeout \"30s\" --drain-timeout \"30s\" --buffer-requests --buffer-responses --log-request-header \"Cache-Control\" --log-request-header \"Last-Modified\" --log-request-header \"User-Agent\"",
+      new_command.deploy(target: "172.1.0.2").join(" ")
+  end
+
+  test "remove" do
+    assert_equal \
+      "docker exec kamal-proxy kamal-proxy remove app-web --target \"172.1.0.2:80\"",
+      new_command.remove(target: "172.1.0.2").join(" ")
+  end
+
+
 
   test "logs" do
     assert_equal \