chore: configure dependabot with 7-day cooldown and grouped updates

- Add cooldown of 7 days (bake time) before dependabot opens PRs for new versions
- Group all updates per ecosystem into a single PR using wildcard patterns
- Reduces PR noise and ensures new versions have time to stabilize

Author: davidgamero

.github/dependabot.yml

@@ -4,25 +4,61 @@ updates:
     directory: /
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7
+    groups:
+      go-dependencies:
+        patterns:
+          - "*"
   - package-ecosystem: "github-actions"
     directory: ".github/workflows"
     schedule:
       interval: weekly
+    cooldown:
+      default-days: 7
+    groups:
+      github-actions:
+        patterns:
+          - "*"
   - package-ecosystem: "github-actions"
     directory: "/template/workflows/helm/.github/workflows"
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7
+    groups:
+      github-actions:
+        patterns:
+          - "*"
   - package-ecosystem: "github-actions"
     directory: "/template/workflows/kustomize/.github/workflows"
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7
+    groups:
+      github-actions:
+        patterns:
+          - "*"
   - package-ecosystem: "github-actions"
     directory: "/template/workflows/manifests/.github/workflows"
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7
+    groups:
+      github-actions:
+        patterns:
+          - "*"
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7
+    groups:
+      github-actions:
+        patterns:
+          - "*"
     labels:
       - "dependencies"