Add Dependabot configuration for automated dependency updates

This configuration file sets up Dependabot to manage dependencies for GitHub Actions and Python packages. It schedules daily updates for both ecosystems and limits the number of open pull requests for Python packages to one. This ensures dependencies are kept up to date continually and systematically.

.github/dependabot.yml

@@ -0,0 +1,19 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    target-branch: main
+    schedule:
+      interval: "daily"
+      time: "00:00"
+    groups:
+      all-actions:
+        patterns: [ "*" ]
+
+  - package-ecosystem: "pip"
+    directory: "/"
+    target-branch: main
+    schedule:
+      interval: "daily"
+      time: "00:00"
+    open-pull-requests-limit: 1