Add frontend dependency update workflows

Adds two scheduled workflows that consume the reusable pnpm
dependency-update workflow from equinor/armada and open a PR with
the result:

- Monthly pnpm update (1st of each month)
- Weekday pnpm audit --fix (Mon-Fri 06:05 UTC, plus push to main)

Resolves: #359

Author: aeshub

.github/workflows/frontend_dependency_security_fix.yml

@@ -0,0 +1,24 @@
+name: Frontend dependency security fix and create PR
+
+on:
+  push:
+    branches:
+      - main
+
+  schedule:
+    - cron: "5 6 * * 1-5" # At 06:05 on every day-of-week from Monday through Friday
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  audit-fix:
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: equinor/armada/.github/workflows/pnpm_dependency_update_and_create_pr.yml@main
+    with:
+      working-directory: frontend
+      node-version: "24"
+      operation: audit-fix

.github/workflows/monthly_frontend_dependency_update.yml

@@ -0,0 +1,21 @@
+name: Monthly frontend dependency update and create PR
+
+on:
+  schedule:
+    - cron: "0 8 1 * *" # 08:00 UTC on the 1st of every month
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  update:
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: equinor/armada/.github/workflows/pnpm_dependency_update_and_create_pr.yml@main
+    with:
+      working-directory: frontend
+      node-version: "24"
+      operation: update