flake.lock: Update

Flake lock file updates:

```
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/26d499fc9f1d567283d5d56fcf367edd815dba1d' (2025-04-12)
  → 'github:nixos/nixpkgs/b000159bba69b0106a42f65e52dbf27f77aca9d3' (2025-04-29)
• Updated input 'nixpkgs-unstable':
    'github:nixos/nixpkgs/b024ced1aac25639f8ca8fdfc2f8c4fbd66c48ef' (2025-04-17)
  → 'github:nixos/nixpkgs/46e634be05ce9dc6d4db8e664515ba10b78151ae' (2025-04-29)
```

flake.lock

@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1745742390,
-        "narHash": "sha256-1rqa/XPSJqJg21BKWjzJZC7yU0l/YTVtjRi0RJmipus=",
+        "lastModified": 1745921652,
+        "narHash": "sha256-hEAvEN+y/OQ7wA7+u3bFJwXSe8yoSf2QaOMH3hyTJTQ=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "26245db0cb552047418cfcef9a25da91b222d6c7",
+        "rev": "b000159bba69b0106a42f65e52dbf27f77aca9d3",
         "type": "github"
       },
       "original": {
@@ -36,11 +36,11 @@
     },
     "nixpkgs-unstable": {
       "locked": {
-        "lastModified": 1745526057,
-        "narHash": "sha256-ITSpPDwvLBZBnPRS2bUcHY3gZSwis/uTe255QgMtTLA=",
+        "lastModified": 1745930157,
+        "narHash": "sha256-y3h3NLnzRSiUkYpnfvnS669zWZLoqqI6NprtLQ+5dck=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "f771eb401a46846c1aebd20552521b233dd7e18b",
+        "rev": "46e634be05ce9dc6d4db8e664515ba10b78151ae",
         "type": "github"
       },
       "original": {