4.x Health endpoint lost its no-cache settings from 3.x

[tjquinno]

Environment Details

• Helidon Version: 4.x
• Helidon SE or Helidon MP
• JDK version:
• OS:
• Docker version (if applicable):

---

Problem Description

See #4241

Apparently this fix in 3.x for health was lost in the conversion to observers.

Steps to reproduce

Run a Helidon server (such as the SE or MP QuickStart app) with health support, access the health endpoint, and inspect the returned headers.

< HTTP/1.1 204 No Content
< Date: Mon, 20 Jan 2025 16:53:35 -0600
< Connection: keep-alive
< Content-Length: 0
<

Compare to the headers returned from the metrics endpoint:

< HTTP/1.1 200 OK
< Date: Mon, 20 Jan 2025 16:52:49 -0600
< Cache-Control: no-cache
< Cache-Control: no-store
< Cache-Control: must-revalidate
< Cache-Control: no-transform
< Connection: keep-alive
< Content-Length: 7118
< Content-Type: text/plain
<