fix: resolve evaluation purity, missing packages, and brittle paths

lib/default.nix

@@ -9,12 +9,7 @@ let
   # Unified state reading function
   # Handles both JSON and plain text files with graceful fallbacks
   readState = { file, default }:
-    let 
-      # In pure evaluation mode (like nix build .#vm), absolute paths as strings
-      # will cause an error in pathExists/readFile.
-      isFileSafe = ! (builtins.isString file && lib.hasPrefix "/" file);
-    in
-    if isFileSafe && builtins.pathExists file then
+    if builtins.pathExists file then
       let
         content = builtins.readFile file;
         cleanContent = lib.removeSuffix "\n" content;