fix: resolve code quality issues, add CI, and improve maintainability

- Remove useless nixConfig block (cache.nixos.org is default)
- Remove manual container-use override; let blueprint auto-discover it
- Add nixosModules.default so README example works
- Fix default launcher: use correct parameterized flake URL
- Replace deprecated sha256 with hash in goose-cli fetchers
- Fix LIBCLANG_PATH to include /lib subdirectory for libclang.so
- Drop --release from goose-cli tests (faster, more debug info)
- Use builtins.toFile in flake-inputs to avoid ARG_MAX risk
- Add lib.warn when overlay has no packages for a system
- Add passthru.updateScript to goose-cli, container-use, skillsmcp
- Fix skillsmcp version to 0.2.0+unstable (pinned to commit, not tag)
- Replace with lib; with explicit references in all meta blocks
- Add update.py script for goose-cli (referenced in AGENTS.md)
- Expand .gitignore with result-* and .direnv/
- Add GitHub Actions CI workflow (nix flake check + build)

packages/container-use/package.nix

@@ -21,6 +21,8 @@ buildGoModule rec {
 
   subPackages = [ "cmd/container-use" ];
 
+  # Tests require network access to container registries and a running
+  # Docker engine, neither of which are available in the Nix sandbox
   doCheck = false;
 
   postInstall = ''
@@ -31,12 +33,20 @@ buildGoModule rec {
     "-s -w -X main.version=v${version}"
   ];
 
-  meta = with lib; {
+  passthru = {
+    updateScript = [
+      "nix-update"
+      "--flake"
+      ".#container-use"
+    ];
+  };
+
+  meta = {
     description = "Containerized environments for coding agents";
     homepage = "https://github.com/dagger/container-use";
     changelog = "https://github.com/dagger/container-use/releases/tag/v${version}";
-    license = licenses.asl20;
+    license = lib.licenses.asl20;
     mainProgram = "container-use";
-    platforms = platforms.linux ++ platforms.darwin;
+    platforms = lib.platforms.linux ++ lib.platforms.darwin;
   };
 }