docs/flake.lock: Update

Flake lock file updates:

• Updated input 'tgirlpkgs':
'path:../.?lastModified=0&narHash=sha256-QI6keeUw3QNLMJ50HwjcNhKfzVk8ciG2XTgEMjjod9Y%3D' (1970-01-01)
→ 'path:../.?lastModified=0&narHash=sha256-H8HYD1LapUfuNpgRhwFoLkQWO7iTjIEsq75rr2RjLus%3D' (1970-01-01)
• Updated input 'tgirlpkgs/nixpkgs':
'https://releases.nixos.org/nixpkgs/nixpkgs-26.05pre918100.0744ef1b047f/nixexprs.tar.xz?lastModified=1766996594&narHash=sha256-Ot0xSLsfRXy6IlMvnc8hSLHKNn/7R8yFDc7uI5Cjpr4%3D&rev=0744ef1b047f07d31d9962d757ffe38ec14a4d41' (2025-12-29)
→ 'https://releases.nixos.org/nixpkgs/nixpkgs-26.05pre918255.346dd96ad74d/nixexprs.tar.xz?lastModified=1767026758&narHash=sha256-OuZZ71OA/6fZePPqgVinI4QVu9j1QCt%2BQ9i5ZgmSGqI%3D&rev=346dd96ad74dc4457a9db9de4f4f57dab2e5731d' (2025-12-29)

docs/flake.lock

···
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1766996594,
-        "narHash": "sha256-Ot0xSLsfRXy6IlMvnc8hSLHKNn/7R8yFDc7uI5Cjpr4=",
-        "rev": "0744ef1b047f07d31d9962d757ffe38ec14a4d41",
+        "lastModified": 1767026758,
+        "narHash": "sha256-OuZZ71OA/6fZePPqgVinI4QVu9j1QCt+Q9i5ZgmSGqI=",
+        "rev": "346dd96ad74dc4457a9db9de4f4f57dab2e5731d",
         "type": "tarball",
-        "url": "https://releases.nixos.org/nixpkgs/nixpkgs-26.05pre918100.0744ef1b047f/nixexprs.tar.xz?lastModified=1766996594&rev=0744ef1b047f07d31d9962d757ffe38ec14a4d41"
+        "url": "https://releases.nixos.org/nixpkgs/nixpkgs-26.05pre918255.346dd96ad74d/nixexprs.tar.xz?lastModified=1767026758&rev=346dd96ad74dc4457a9db9de4f4f57dab2e5731d"
       },
       "original": {
         "type": "tarball",
···
       },
       "locked": {
         "lastModified": 0,
-        "narHash": "sha256-QI6keeUw3QNLMJ50HwjcNhKfzVk8ciG2XTgEMjjod9Y=",
+        "narHash": "sha256-H8HYD1LapUfuNpgRhwFoLkQWO7iTjIEsq75rr2RjLus=",
         "path": "../.",
         "type": "path"
       },