Add navi deployment module and integrate SSH inventory for remote management

- Introduced a new `navi` module for managing deployments across multiple hosts.
- Enhanced SSH inventory management to support public key application for authorized hosts.
- Configured system deployment builder for seamless integration with Navi.
- Updated various host configurations to enable deployment capabilities and streamline SSH access.

modules/lib/navi-hive.nix

@@ -0,0 +1,33 @@
+# Build a raw Navi hive attrset from host specs + deployment targets.
+# Call `inputs.navi.lib.makeHive` on the result to produce `flake.naviHive`.
+{ lib, inputs, ... }: {
+  flake.lib.mkNaviHiveConfig =
+    {
+      metaNixpkgs,
+      hostSpecs,
+      deployments,
+    }:
+    let
+      deployNodes = lib.filterAttrs (name: _: deployments ? ${name}) hostSpecs;
+    in
+    {
+      meta = {
+        nixpkgs = metaNixpkgs;
+        nodeNixpkgs = lib.mapAttrs (
+          name: spec:
+          import inputs.nixpkgs {
+            system = spec.system;
+          }
+        ) deployNodes;
+        nodeSpecialArgs = lib.mapAttrs (_: spec: spec.specialArgs) deployNodes;
+        allowApplyAll = false;
+      };
+    }
+    //     lib.mapAttrs (
+      name: spec:
+      {
+        imports = spec.modules or [ spec.configuration ];
+        deployment = deployments.${name};
+      }
+    ) deployNodes;
+}