feat: add renovate configuration

This commit introduces a new configuration for Renovate bot. It includes
settings for vulnerability alerts, label management, schema, range strategy,
lock file maintenance, platform automerge, dependency dashboard, automerge,
branch concurrent limit, and stability days.

.github/renovate.json

@@ -0,0 +1,21 @@
+{
+  "vulnerabilityAlerts": {
+    "labels": [
+      "security"
+    ]
+  },
+  "labels": [
+    "dependencies",
+    "renovate"
+  ],
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "rangeStrategy": "bump",
+  "lockFileMaintenance": {
+    "enabled": true
+  },
+  "platformAutomerge": true,
+  "dependencyDashboard": false,
+  "automerge": true,
+  "branchConcurrentLimit": 0,
+  "stabilityDays": 3
+}