refactor: remove deployment.json and use direct selectors

- Remove deployment.json file generation from outputs.nix
- Add throw for deprecated deployment.file usage with upgrade instructions
- Remove vars data from deployment.data
- Update Machine class to use direct select() calls instead of deployment property
- Update all deployment property accesses to use direct selectors
- Add precaching for frequently accessed values in update.py:
  - Module paths for facts and vars
  - Deployment settings (requireExplicitUpdate, nixosMobileWorkaround)
  - Services and generators data
  - Secret upload locations
- This removes unnecessary JSON serialization and makes the code more composable

checks/backups/flake-module.nix

@@ -22,7 +22,6 @@
         dependencies = [
           self
           pkgs.stdenv.drvPath
-          self.clan.clanInternals.machines.${pkgs.hostPlatform.system}.test-backup.config.system.clan.deployment.file
         ] ++ builtins.map (i: i.outPath) (builtins.attrValues self.inputs);
         closureInfo = pkgs.closureInfo { rootPaths = dependencies; };
       in

checks/flash/flake-module.nix

@@ -50,7 +50,6 @@
         self.nixosConfigurations."test-flash-machine-${pkgs.hostPlatform.system}".config.system.build.toplevel
         self.nixosConfigurations."test-flash-machine-${pkgs.hostPlatform.system}".config.system.build.diskoScript
         self.nixosConfigurations."test-flash-machine-${pkgs.hostPlatform.system}".config.system.build.diskoScript.drvPath
-        self.nixosConfigurations."test-flash-machine-${pkgs.hostPlatform.system}".config.system.clan.deployment.file
       ] ++ builtins.map (i: i.outPath) (builtins.attrValues self.inputs);
       closureInfo = pkgs.closureInfo { rootPaths = dependencies; };
     in

checks/installation/flake-module.nix

@@ -10,7 +10,6 @@ let
       dependencies = [
         self.clan.clanInternals.machines.${pkgs.hostPlatform.system}.test-install-machine-with-system.config.system.build.toplevel
         self.clan.clanInternals.machines.${pkgs.hostPlatform.system}.test-install-machine-with-system.config.system.build.diskoScript
-        self.clan.clanInternals.machines.${pkgs.hostPlatform.system}.test-install-machine-with-system.config.system.clan.deployment.file
         pkgs.stdenv.drvPath
         pkgs.bash.drvPath
         pkgs.nixos-anywhere

checks/morph/flake-module.nix

@@ -35,7 +35,6 @@
                   pkgs.stdenv.drvPath
                   pkgs.stdenvNoCC
                   self.nixosConfigurations.test-morph-machine.config.system.build.toplevel
-                  self.nixosConfigurations.test-morph-machine.config.system.clan.deployment.file
                 ] ++ builtins.map (i: i.outPath) (builtins.attrValues self.inputs);
                 closureInfo = pkgs.closureInfo { rootPaths = dependencies; };
               in