chore: update all dependencies and add grouped dependabot config

Update uv.lock with latest dependency versions, superseding the
individual dependabot PRs (#581, #582, #583).

Add .github/dependabot.yml with grouped updates so future dependency
bumps arrive as a single weekly PR instead of one PR per package.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: gijzelaerr

.github/dependabot.yml

@@ -0,0 +1,27 @@
+version: 2
+updates:
+  - package-ecosystem: "uv"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+    groups:
+      all-dependencies:
+        patterns:
+          - "*"
+    commit-message:
+      prefix: "chore"
+      include: "scope"
+
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+    groups:
+      all-actions:
+        patterns:
+          - "*"
+    commit-message:
+      prefix: "chore"
+      include: "scope"