Change caddy to run on non privileged ports (#1106)

## Summary
Change caddy to run on non privileged ports. I added the following
script to the caddy example:
- devbox run start

Since I have a global caddy running on port `2019` for the admin
endpoint already, I need to run this caddy under a separate admin port.

## Issue I still need help with (resolved. See commit "fix process
compose")
Running `devbox services up` has the following error
```
[caddy_1	] Error: loading initial config: loading new config: starting caddy administration endpoint: listen tcp 127.0.0.1:2019: bind: address already in use
```
Where as `devbox run start` is successful 🤷‍♀️ Are we doing something
special with process compose? Seems like for some reason, it is loading
some initial config, then reload it with the new config. And because the
initial config has a port conflict, everything fails.

To reproduce, go to
[https://devbox.sh/github.com/jetpack-io/devbox?folder=examples/servers/caddy&branch=lucille--caddy-on-vm](https://devbox.sh/github.com/jetpack-io/devbox?folder=examples/servers/caddy&branch=lucille--caddy-on-vm)

## How was it tested?
devbox.sh

Author: LucilleH

examples/servers/caddy/README.md

@@ -4,13 +4,14 @@
 
 You can customize the config used by the caddy service by modifying the Caddyfile in devbox.d/caddy, or by changing the CADDY_CONFIG environment variable to point to a custom config. The custom config must be either JSON or Caddyfile format.
 
-After starting the service, you can test this example using `curl https://localhost:2020`
+After starting the service, you can test this example using `curl http://localhost:8082`
 
 ## Services
 
 * caddy
 
-Use `devbox services start|stop [service]` to interact with services
+Use `devbox run start` to start the caddy server.
+You can also use `devbox services start|stop [service]` to interact with services.
 
 ## This plugin creates the following helper files
 

examples/servers/caddy/devbox.d/caddy/Caddyfile

@@ -1,9 +1,15 @@
 # See https://caddyserver.com/docs/caddyfile for more details
+{
+	admin 0.0.0.0:2020
+	auto_https disable_certs
+	http_port 8800
+	https_port 4443
+}
 
-localhost:2020 {
-        root * {$CADDY_ROOT_DIR}
-        log {
-            output file {$CADDY_LOG_DIR}/caddy.log
-        }
-        file_server
-}
+:8082 {
+	root * {$CADDY_ROOT_DIR}
+	log {
+		output file {$CADDY_LOG_DIR}/caddy.log
+	}
+	file_server
+}

examples/servers/caddy/devbox.json

@@ -3,6 +3,9 @@
     "caddy@latest"
   ],
   "shell": {
-    "init_hook": null
+    "init_hook": null,
+    "scripts": {
+      "start": "caddy run --config=devbox.d/caddy/Caddyfile"
+    }
   }
 }

examples/servers/caddy/devbox.lock

@@ -3,6 +3,7 @@
   "packages": {
     "caddy@latest": {
       "last_modified": "2023-05-01T16:53:22Z",
+      "plugin_version": "0.0.2",
       "resolved": "github:NixOS/nixpkgs/8670e496ffd093b60e74e7fa53526aa5920d09eb#caddy",
       "version": "2.6.4"
     }

plugins/caddy.json

@@ -1,6 +1,6 @@
 {
     "name": "caddy",
-    "version": "0.0.1",
+    "version": "0.0.2",
     "readme": "You can customize the config used by the caddy service by modifying the Caddyfile in devbox.d/caddy, or by changing the CADDY_CONFIG environment variable to point to a custom config. The custom config must be either JSON or Caddyfile format.",
     "env": {
         "CADDY_CONFIG": "{{ .DevboxDir }}/Caddyfile",

plugins/caddy/Caddyfile

@@ -1,9 +1,15 @@
 # See https://caddyserver.com/docs/caddyfile for more details
+{
+	admin 0.0.0.0:2020
+	auto_https disable_certs
+	http_port 8800
+	https_port 4443
+}
 
-localhost:2020 {
-        root * {$CADDY_ROOT_DIR}
-        log {
-            output file {$CADDY_LOG_DIR}/caddy.log
-        }
-        file_server
-}
+:8082 {
+	root * {$CADDY_ROOT_DIR}
+	log {
+		output file {$CADDY_LOG_DIR}/caddy.log
+	}
+	file_server
+}

plugins/caddy/process-compose.yaml

@@ -2,7 +2,7 @@ version: "0.6"
 
 processes:
   caddy:
-    command: "caddy run --config=$CADDY_CONF"
+    command: "caddy run --config=$CADDY_CONFIG"
     availability:
       restart: on_failure
       max_restarts: 5