feat(claude): add caveman and oh-my-claudecode skills via flake inputs

Declaratively manage Claude Code skills through home-manager by fetching
plugin repos as non-flake inputs and symlinking their skills directories.

flake.nix

@@ -9,9 +9,17 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
     kickstart-nvim.url = "github:0xWheatyz/kickstart.nvim";
+    caveman = {
+      url = "github:JuliusBrussee/caveman";
+      flake = false;
+    };
+    oh-my-claudecode = {
+      url = "github:Yeachan-Heo/oh-my-claudecode";
+      flake = false;
+    };
   };
 
-  outputs = { self, nixpkgs, nixpkgs-unstable, home-manager, kickstart-nvim, ... }:
+  outputs = { self, nixpkgs, nixpkgs-unstable, home-manager, kickstart-nvim, caveman, oh-my-claudecode, ... }:
     let
       system = "x86_64-linux";
       pkgs-unstable = import nixpkgs-unstable {
@@ -31,7 +39,7 @@
             home-manager.useUserPackages = true;
             home-manager.users.l-wyatt = import ./home.nix;
             home-manager.extraSpecialArgs = {
-              inherit kickstart-nvim;
+              inherit kickstart-nvim caveman oh-my-claudecode;
             };
             home-manager.sharedModules = [
               kickstart-nvim.homeManagerModules.default