Docker invocations need mapped volume

So prefs can be persisted.

Add a `debug platform` command.

Makefile

@@ -72,7 +72,7 @@ docker-run-version:
 	@docker run -it webhookdb-cli version --time
 
 docker-run-%:
-	@docker run -it webhookdb-cli $(*)
+	@docker run -v ~/.webhookdb/dockercli:/root -it webhookdb-cli $(*)
 
 dockerhub-run-version:
 	@docker run -it webhookdb/webhookdb-cli:latest version --time

README.md

@@ -18,11 +18,12 @@ so you have immediate, reliable access to all your data.
 
 ## Installing
 
-Use the docker container:
+Use the docker container (note you need to mount `/root` to persist auth info between invocations):
 
 ```
 $ docker run -it webhookdb/webhookdb-cli:latest version
 0.13.0 (acb64d0f)
+$ docker run -v ~/.webhookdb/dockercli:/root -it webhookdb/webhookdb-cli:latest auth login
 ```
 
 On MacOS, install from Homebrew:

cmd/cmd_debug.go

@@ -74,6 +74,18 @@ var debugCmd = &cli.Command{
 				return nil
 			}),
 		},
+		{
+			Name:  "platform",
+			Usage: "Print out information about the current platform.",
+			Action: cliAction(func(c *cli.Context, ac appcontext.AppContext, ctx context.Context) error {
+				home, err := ac.FS.UserHomeDir()
+				if err != nil {
+					home = fmt.Sprintf("error: %s", err)
+				}
+				fmt.Fprintf(c.App.Writer, "Home: %s\n", home)
+				return nil
+			}),
+		},
 		{
 			Name:  "update-auth-display",
 			Usage: "Used to update the WASM terminal on startup.",