Upgrade Janus and FreePBX containers from Debian 11

[Stell0]

Migrate the Janus and FreePBX images to a supported Debian release. Debian 11 (Bullseye) reached the end of Debian LTS support on August 31, 2026. ([Debian]1)

The affected images are:

• ghcr.io/nethesis/nethvoice-janus: janus/Containerfile uses debian:bullseye-slim for both builder and runtime stages.
• ghcr.io/nethesis/nethvoice-freepbx: freepbx/Containerfile uses debian:11 for the builder and php:7.4-apache for the runtime, whose APT configuration also resolves to Bullseye according to the reported inspection.

Update both stages of each image, including the FreePBX PHP runtime base and any dependencies required by the Debian upgrade.

Steps to reproduce

1. Check out ns8-nethvoice.
2. Rebuild the Janus and FreePBX images without cached layers.
3. Observe the APT operations against Bullseye repositories during the builds.

Expected behavior

Both images use supported Debian bases, build without APT repository errors, and preserve existing Janus and FreePBX functionality.

Actual behavior

Both images still depend on Bullseye. Repository failures are reported for both affected images.

See also

Nethesis ns8-nethvoice repository. ([github.com]2)