chore: remove goose-cli package and cleanup configuration

- Delete packages/goose-cli/ (librusty_v8 pre-built binary dependency)
- Remove global nixpkgs.config.allowUnfree from flake.nix
  (goose-cli was the only package requiring unfree binaries)
- Add .claude/ to .gitignore
- Update README.md and AGENTS.md to remove all goose-cli references

flake.nix

@@ -33,9 +33,6 @@
     let
       blueprintOutputs = inputs.blueprint {
         inherit inputs;
-        # allowUnfree is needed for packages that depend on pre-built
-        # binaries (e.g., goose-cli's librusty_v8)
-        nixpkgs.config.allowUnfree = true;
       };
     in
     blueprintOutputs