User-facing polish to match the element-calling port changes:
- helpers.js: port-forward guide example now shows the 40000-40099 range
instead of the removed 30000-40000.
- versions.json: livekit dev fallback 1.5.2 -> 1.13.6 (the Nix-generated
version in sovran-hub.nix already derives from pkgs.livekit.version).
- server.py: docstring/comment examples reference 40000-40099.
- CHANGELOG.md: record the calling changes under [Unreleased].
The tile/modal port tables themselves are data-driven from server.py's
port_requirements / _PORTS_ELEMENT_CALLING (updated in the previous commit),
so no further UI changes are needed.
Fix the version metadata generation in sovran-hub.nix for Alby Hub, RTL, and Mempool. Previously, the build would incorrectly fall back to older upstream nixpkgs versions because the package names exist upstream, despite the OS deploying custom vendored forks locally. This replaces the fragile checks with direct evaluations of the local packages.
Also updates the development fallback versions.json to reflect the current vendored Alby Hub version (1.24.0).