chore(maestro): track the maestro flake from main

The nix branch landed, so the ?ref pin is no longer needed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

flake.lock

@@ -753,16 +753,15 @@
         "nixpkgs": "nixpkgs_6"
       },
       "locked": {
-        "lastModified": 1787392420,
+        "lastModified": 1787392581,
-        "narHash": "sha256-oe527mGQibglnODuZk/u1WKInMGF6/hc6YPATNOGgOs=",
+        "narHash": "sha256-8S3IVtvYjLbAfK7w+RELpLFnaJOEOSCy44LjDeJUJpI=",
-        "ref": "nix",
+        "ref": "refs/heads/main",
-        "rev": "401afbc8125b1a17b339559e1f93d967269cd25c",
+        "rev": "c5d7a6bf805ee06cdcd9b3c276f6c2681bfdd2de",
-        "revCount": 206,
+        "revCount": 211,
         "type": "git",
         "url": "https://git.naps.pt/naps62/maestro.git"
       },
       "original": {
-        "ref": "nix",
         "type": "git",
         "url": "https://git.naps.pt/naps62/maestro.git"
       }

flake.nix

@@ -72,8 +72,7 @@
     agent-skills.url = "git+https://git.naps.pt/yolo/agent-skills.git";
     # Terminal-session orchestrator. Pins its own nixpkgs for the same reason
     # ethui and agent-of-empires do — it is a verified Rust build.
-    # TODO: drop ?ref=nix once that branch lands on main.
+    maestro.url = "git+https://git.naps.pt/naps62/maestro.git";
-    maestro.url = "git+https://git.naps.pt/naps62/maestro.git?ref=nix";
     nix-index-database = {
       url = "github:nix-community/nix-index-database";
       inputs.nixpkgs.follows = "nixpkgs";