Updated all flake inputs and applied srveral improvements to the
system configurations.
*** Updates
- Ran =flake update= to bring all dependencies to their latest
versions.
- Pinned =lix-module= to the stable =release-2.93= branch to
prevent breakages from its main branch.
*** System Configuration
- ssh: Reworked the client configuration to use a global =*= match
block for secure defaults. Disabled the default home-manager
config for removing nixpkgs' wrannings.
- intel-vaapi-driver: Enabled =enableHybridCodec= override to avoid
to build whole package from scratch.
- kde: Forced the Qt platform theme to =kde= to fix a visual bug
with Stylix.
- onnxruntime: Disabled CUDA/NCCL support to avoid to build the
whole package from scratch.
*** Application Changes
- firefox: Switched the default browser package to =firefox-beta=
across the entire configuration (NixOS, home-manager, and niri).
- editor: Removed =hurl= and =cmake-language-server= from the
editor runtime environment for broken packages.
