flake: use nixpkgs for jujutsu input

flake.lock

@@ -177,7 +177,9 @@
     "jujutsu": {
       "inputs": {
         "flake-utils": "flake-utils_2",
-        "nixpkgs": "nixpkgs_3",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
         "rust-overlay": "rust-overlay"
       },
       "locked": {
@@ -295,22 +297,6 @@
       }
     },
     "nixpkgs_3": {
-      "locked": {
-        "lastModified": 1731890469,
-        "narHash": "sha256-D1FNZ70NmQEwNxpSSdTXCSklBH1z2isPR84J6DQrJGs=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "5083ec887760adfe12af64830a66807423a859a7",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixpkgs-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs_4": {
       "locked": {
         "lastModified": 1740603184,
         "narHash": "sha256-t+VaahjQAWyA+Ctn2idyo1yxRIYpaDxMgHkgCNiMJa4=",
@@ -335,7 +321,7 @@
         "jujutsu": "jujutsu",
         "lix-module": "lix-module",
         "nixos-hardware": "nixos-hardware",
-        "nixpkgs": "nixpkgs_4",
+        "nixpkgs": "nixpkgs_3",
         "nixpkgs-unstable-small": "nixpkgs-unstable-small"
       }
     },

flake.nix

@@ -60,6 +60,7 @@
       owner = "jj-vcs";
       repo = "jj";
       ref = "v0.26.0";
+      inputs.nixpkgs.follows = "nixpkgs";
     };
   };