Fix flake-lock: enable experimental features, update lockfile

The nixos/nix container doesn't have flakes enabled by default.
Pass --extra-experimental-features flag. Also commit the updated
flake.lock with home-manager input resolved via Dagger.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.dagger/src/blumeops_ci/main.py

@@ -80,6 +80,15 @@ class BlumeopsCi:
             .from_(NIX_IMAGE)
             .with_directory("/workspace", src)
             .with_workdir(f"/workspace/{flake_path}")
-            .with_exec(["nix", "flake", "lock", "--accept-flake-config"])
+            .with_exec(
+                [
+                    "nix",
+                    "--extra-experimental-features",
+                    "nix-command flakes",
+                    "flake",
+                    "lock",
+                    "--accept-flake-config",
+                ]
+            )
             .file(f"/workspace/{flake_path}/flake.lock")
         )

nixos/ringtail/flake.lock

@@ -20,6 +20,27 @@
         "type": "github"
       }
     },
+    "home-manager": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1770260404,
+        "narHash": "sha256-3iVX1+7YUIt23hBx1WZsUllhbmP2EnXrV8tCRbLxHc8=",
+        "owner": "nix-community",
+        "repo": "home-manager",
+        "rev": "0d782ee42c86b196acff08acfbf41bb7d13eed5b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "ref": "release-25.11",
+        "repo": "home-manager",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1771208521,
@@ -39,6 +60,7 @@
     "root": {
       "inputs": {
         "disko": "disko",
+        "home-manager": "home-manager",
         "nixpkgs": "nixpkgs"
       }
     }