- Deleted `environment.shellInit` previously used for Nix path initialization in SSH sessions.
- Path initialization is now fully handled by `programs.fish.loginShellInit` for consistency across environments.
- Added `sshKey` field for all builder configurations in `nixbuild.nix` to standardize access keys.
- Replaced `programs.fish.shellInit` with `environment.shellInit` and introduced `programs.fish.loginShellInit` for improved Nix path initialization.
- Updated multiple Flake lockfile entries to the latest revisions for improved consistency with upstream changes.
- Removed redundant `sshKey` fields from builder configurations in `nixbuild.nix`.
- Added `Nix` path initialization for fish shell SSH sessions and refactored mouse bindings in `default.nix`.
- Moved shared distributed build settings to `nixbuild.nix` for reuse.
- Updated `m4` and `rialo` systems to import the centralized configuration.
- Simplifies maintenance and ensures consistency across systems.
