Dependabot: update all dev dependencies on a monthly basis

Patch and minor updates will be grouped in the same MRs.
Major updates will result in standalone MRs.

Also, since only two schedules are currently supported for each package-ecosystem,
the update frequency of noble and fflate has been changed to a daily one
(same as playwright).

.github/dependabot.yml

@@ -10,16 +10,15 @@ updates:
       interval: "daily"
     allow:
       - dependency-name: "playwright"
-    versioning-strategy: increase
-
-  - package-ecosystem: "npm"
-    directory: "/"
-    schedule:
-      interval: "weekly"
-    allow:
       - dependency-name: "@noble*"
       - dependency-name: "fflate"
     versioning-strategy: increase
+    cooldown: # consider updates only X days after release
+      semver-major-days: 7
+      semver-minor-days: 1
+      semver-patch-days: 1
+      include:
+        - "*"
     groups:
       # Any packages matching the pattern @noble* where the highest resolvable
       # version is minor or patch will be grouped together.
@@ -31,3 +30,27 @@ updates:
         update-types:
         - "minor"
         - "patch"
+  # update other dependencies separately on a monthly basis
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "monthly"
+    ignore: # targeted by other schedule above
+      - dependency-name: "playwright"
+      - dependency-name: "@noble*"
+      - dependency-name: "fflate"
+    versioning-strategy: increase
+    cooldown: # consider updates only X days after release
+      semver-major-days: 30
+      semver-minor-days: 3
+      semver-patch-days: 3
+      include:
+        - "*"
+    groups:
+      dev-dependencies:
+        applies-to: version-updates
+        patterns:
+          - "*"
+        update-types: # major updates will trigger non-grouped MRs
+          - "minor"
+          - "patch"