Add renovate.json

Automated changes by the
[update-flake-lock](https://github.com/DeterminateSystems/update-flake-lock)
GitHub Action.

```
Flake lock file updates:

• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/aca4d95' (2026-03-06)
  → 'github:nixos/nixpkgs/c06b4ae' (2026-03-13)
```

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1772773019,
-        "narHash": "sha256-E1bxHxNKfDoQUuvriG71+f+s/NT0qWkImXsYZNFFfCs=",
+        "lastModified": 1773389992,
+        "narHash": "sha256-wvfdLLWJ2I9oEpDd9PfMA8osfIZicoQ5MT1jIwNs9Tk=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "aca4d95fce4914b3892661bcb80b8087293536c6",
+        "rev": "c06b4ae3d6599a672a6210b7021d699c351eebda",
         "type": "github"
       },
       "original": {

renovate.json

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "config:recommended"
+  ]
+}