chore: add Dependabot config (#3)

Weekly Monday 06:00 America/Toronto runs across the manifest
ecosystems present in this repo plus GitHub Actions, with
grouped @types/* updates where applicable so security advisories
don't get buried under one-PR-per-package noise.

Author: Zawwarsami16

.github/dependabot.yml

@@ -0,0 +1,30 @@
+version: 2
+updates:
+  - package-ecosystem: pip
+    directory: "/"
+    schedule:
+      interval: weekly
+      day: monday
+      time: "06:00"
+      timezone: America/Toronto
+    open-pull-requests-limit: 5
+    labels:
+      - dependencies
+      - python
+    commit-message:
+      prefix: deps
+      include: scope
+
+  - package-ecosystem: github-actions
+    directory: "/"
+    schedule:
+      interval: weekly
+      day: monday
+      time: "06:00"
+      timezone: America/Toronto
+    open-pull-requests-limit: 3
+    labels:
+      - dependencies
+      - github-actions
+    commit-message:
+      prefix: ci