flake.lock: Update

Flake lock file updates:

```
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/26d499fc9f1d567283d5d56fcf367edd815dba1d' (2025-04-12)
  → 'github:nixos/nixpkgs/1d3aeb5a193b9ff13f63f4d9cc169fb88129f860' (2025-05-06)
• Updated input 'nixpkgs-unstable':
    'github:nixos/nixpkgs/b024ced1aac25639f8ca8fdfc2f8c4fbd66c48ef' (2025-04-17)
  → 'github:nixos/nixpkgs/3730d8a308f94996a9ba7c7138ede69c1b9ac4ae' (2025-05-05)
```

flake.lock

@@ -36,11 +36,11 @@
     },
     "nixpkgs-unstable": {
       "locked": {
-        "lastModified": 1746663147,
+        "lastModified": 1746461020,
-        "narHash": "sha256-Ua0drDHawlzNqJnclTJGf87dBmaO/tn7iZ+TCkTRpRc=",
+        "narHash": "sha256-7+pG1I9jvxNlmln4YgnlW4o+w0TZX24k688mibiFDUE=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "dda3dcd3fe03e991015e9a74b22d35950f264a54",
+        "rev": "3730d8a308f94996a9ba7c7138ede69c1b9ac4ae",
         "type": "github"
       },
       "original": {