ci/bindings: build o1js bindings in CI

.github/workflows/build-bindings.yml

@@ -0,0 +1,23 @@
+# Purpose: We want to build the o1js bindings in CI so that people in the 
+# community can change them without being scared of breaking things, or
+# needing to do the complicated (without nix) build setup.
+
+name: Build o1js bindings
+
+on:
+  pull_request:
+
+jobs:  
+  nix-build:
+    name: build-bindings-ubuntu
+    runs-on: ubuntu-latest
+    steps:
+      - name: Disable smudging
+        run: echo "GIT_LFS_SKIP_SMUDGE=1" >> $GITHUB_ENV
+      - uses: actions/checkout@v4
+      - uses: cachix/install-nix-action@v30
+      - run: |
+          set -Eeu
+          export GIT_LFS_SKIP_SMUDGE=1
+          ./pin.sh
+          nix develop o1js --command bash --command "npm run build:update-bindings"

flake.nix

@@ -12,8 +12,10 @@
     dune-nix.inputs.nixpkgs.follows = "nixpkgs";
     dune-nix.inputs.flake-utils.follows = "flake-utils";
     flake-utils.url = "github:numtide/flake-utils";
+    nix-github-actions.url = "github:nix-community/nix-github-actions";
+    nix-github-actions.inputs.nixpkgs.follows = "nixpkgs";
   };
-  outputs = { self, nixpkgs, flake-utils, ... }@inputs:
+  outputs = { self, nixpkgs, nix-github-actions, flake-utils, ... }@inputs:
     flake-utils.lib.eachDefaultSystem (system:
       let
         pkgs= (nixpkgs.legacyPackages."${system}".extend