chore(github): add Dependabot configuration

Enable automated dependency updates for all workspace packages (core,
cli, vscode, claude-plugin), the root workspace, and GitHub Actions. PRs
are grouped by dependency type to reduce noise.

Assisted-by: Claude

Author: otaviof

.github/dependabot.yml

@@ -0,0 +1,56 @@
+---
+version: 2
+updates:
+  - package-ecosystem: npm
+    directory: /
+    schedule:
+      interval: weekly
+    groups:
+      dev-dependencies:
+        dependency-type: development
+      production-dependencies:
+        dependency-type: production
+  - package-ecosystem: npm
+    directory: /packages/core
+    schedule:
+      interval: weekly
+    groups:
+      dev-dependencies:
+        dependency-type: development
+      production-dependencies:
+        dependency-type: production
+  - package-ecosystem: npm
+    directory: /packages/cli
+    schedule:
+      interval: weekly
+    groups:
+      dev-dependencies:
+        dependency-type: development
+      production-dependencies:
+        dependency-type: production
+  - package-ecosystem: npm
+    directory: /packages/vscode
+    schedule:
+      interval: weekly
+    groups:
+      dev-dependencies:
+        dependency-type: development
+      production-dependencies:
+        dependency-type: production
+  - package-ecosystem: npm
+    directory: /packages/claude-plugin
+    schedule:
+      interval: weekly
+    groups:
+      dev-dependencies:
+        dependency-type: development
+      production-dependencies:
+        dependency-type: production
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+    groups:
+      actions:
+        patterns:
+          - "*"