Remove healthcheck from frankenphp configuration (#661)

The CMD healthcheck fails with “executable not found” because the healthcheck binary simply does not exist in the image. There are only the specialized scripts: healthcheck-octane, healthcheck-queue, healthcheck-schedule, healthcheck-horizon, and healthcheck-reverb.

For the default FrankenPHP mode (without Octane), the image already includes a built-in HEALTHCHECK:

curl --insecure http://localhost:${CADDY_HTTP_PORT}${HEALTHCHECK_PATH}

with start_period: 60s, start_interval: 3s, interval: 10s, timeout: 3s, and retries: 3.

Author: emaia

docs/content/docs/2.image-variations/frankenphp.md

@@ -89,11 +89,6 @@ services:
     environment:
       # Use Laravel's built-in health check
       HEALTHCHECK_PATH: /up
-    healthcheck:
-      test: ["CMD", "healthcheck"]
-      interval: 10s
-      timeout: 5s
-      retries: 3
 ```
 
 ::tip
@@ -405,4 +400,4 @@ If you need to customize the container further, reference the docs below:
 - [Environment Variable Specification](/docs/reference/environment-variable-specification) - See which environment variables are available to customize PHP and Caddy settings.
 - [Command Reference](/docs/reference/command-reference) - See which commands are available to run inside the container.
 - [FrankenPHP Documentation](https://frankenphp.dev/){target="_blank"} - Official FrankenPHP documentation for advanced features.
-- [Caddy Documentation](https://caddyserver.com/docs/){target="_blank"} - Official Caddy documentation for web server configuration.
+- [Caddy Documentation](https://caddyserver.com/docs/){target="_blank"} - Official Caddy documentation for web server configuration.