Add configurable proxy timeout via annotations

[PhoenixSolutionsGroup]

Summary

• Add zeropod.ctrox.dev/proxy-timeout annotation to make the activator's proxy timeout configurable
• Defaults to 5s (no behavior change for existing users)
• Follows the same pattern as probe-buffer-size

Motivation

When a restored app depends on a downstream service that also needs to wake up (e.g. a hibernated database), the response can take longer than 5s. The hardcoded timeout kills the proxy conn>

Usage

annotations:
  zeropod.ctrox.dev/proxy-timeout: "30s"

Test plan

• Unit tests for annotation parsing (custom value + default)

Closes #153

[ctrox]

Thanks for the PR, looks good but I think to fix the issue described you also need to make the connectTimeout configurable as that is most likely more relevant while the container is being restored. The proxyTimeout only comes into play after the restored container was able to accept the connection. Would be great if you could also add that.

[PhoenixSolutionsGroup]

Just added the timeout and created defaultProxyTimeout and defaultConnectTimeout :)

[ctrox]

Oh almost forgot, can you also add the new annotaions to the docs? Other than that it looks good to merge, I just triggered the CI.