flake.lock: Update

Flake lock file updates:

```
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/78add7b7abb61689e34fc23070a8f55e1d26185b' (2025-05-28)
  → 'github:nixos/nixpkgs/1f426f65ac4e6bf808923eb6f8b8c2bfba3d18c5' (2025-06-23)
• Updated input 'nixpkgs-unstable':
    'github:nixos/nixpkgs/910796cabe436259a29a72e8d3f5e180fc6dfacc' (2025-05-31)
  → 'github:nixos/nixpkgs/4b1164c3215f018c4442463a27689d973cffd750' (2025-06-24)
• Updated input 'treefmt-nix':
    'github:numtide/treefmt-nix/1f3f7b784643d488ba4bf315638b2b0a4c5fb007' (2025-05-26)
  → 'github:numtide/treefmt-nix/a05be418a1af1198ca0f63facb13c985db4cb3c5' (2025-06-06)
```

flake.lock

@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1751048012,
-        "narHash": "sha256-MYbotu4UjWpTsq01wglhN5xDRfZYLFtNk7SBY0BcjkU=",
+        "lastModified": 1750646418,
+        "narHash": "sha256-4UAN+W0Lp4xnUiHYXUXAPX18t+bn6c4Btry2RqM9JHY=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "a684c58d46ebbede49f280b653b9e56100aa3877",
+        "rev": "1f426f65ac4e6bf808923eb6f8b8c2bfba3d18c5",
         "type": "github"
       },
       "original": {
@@ -36,11 +36,11 @@
     },
     "nixpkgs-unstable": {
       "locked": {
-        "lastModified": 1751011381,
-        "narHash": "sha256-krGXKxvkBhnrSC/kGBmg5MyupUUT5R6IBCLEzx9jhMM=",
+        "lastModified": 1750741721,
+        "narHash": "sha256-Z0djmTa1YmnGMfE9jEe05oO4zggjDmxOGKwt844bUhE=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "30e2e2857ba47844aa71991daa6ed1fc678bcbb7",
+        "rev": "4b1164c3215f018c4442463a27689d973cffd750",
         "type": "github"
       },
       "original": {
@@ -95,11 +95,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1750931469,
-        "narHash": "sha256-0IEdQB1nS+uViQw4k3VGUXntjkDp7aAlqcxdewb/hAc=",
+        "lastModified": 1749194973,
+        "narHash": "sha256-eEy8cuS0mZ2j/r/FE0/LYBSBcIs/MKOIVakwHVuqTfk=",
         "owner": "numtide",
         "repo": "treefmt-nix",
-        "rev": "ac8e6f32e11e9c7f153823abc3ab007f2a65d3e1",
+        "rev": "a05be418a1af1198ca0f63facb13c985db4cb3c5",
         "type": "github"
       },
       "original": {