fix(control-plane-server): forward the proxy settings from the Context

[mlahouar]

Description

The package does not pass .Context.proxy to its chart, so the server pod runs
without HTTP_PROXY, HTTPS_PROXY or NO_PROXY. It reads package schemas from
the OCI registry and talks to Keycloak, so behind a forward proxy both fail.

The chart already renders these variables from .Values.proxy. The package now
declares proxy in its schema.context and feeds the three keys.

Related Issue

Fixes #65

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactor / chore
• Breaking change

How to Test

1. Set proxy.httpProxy and proxy.httpsProxy in the platform Context.
2. Apply the control plane server Release.
3. Read the environment of the server pod.

The pod carries the proxy variables, and their lowercase form.

Checklist

• I have tested my changes
• Documentation updated if needed
• If breaking change: migration path described above
• I hereby declare this contribution to be licensed under the Apache License Version 2.0.
• I hereby agree to grant TOSIT a copyright license to use my contributions.