ci: add scheduled workflow to update tool versions

Runs weekly (Monday 08:00 UTC) and on manual dispatch. Checks
latest releases for Argo, Kargo, and pack CLIs and opens a PR
when updates are available.

https://claude.ai/code/session_01RofXXAMZxK4irobNYjYn3W

Author: claude

.github/workflows/update-tools.yaml

@@ -0,0 +1,101 @@
+name: Update tool versions
+
+on:
+  schedule:
+    - cron: "0 8 * * 1" # Every Monday at 08:00 UTC
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  update-tools:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Fetch latest tool versions
+        id: versions
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          get_latest_version() {
+            local repo="$1"
+            gh api "repos/${repo}/releases/latest" --jq '.tag_name' | sed 's/^v//'
+          }
+
+          ARGO_LATEST=$(get_latest_version "argoproj/argo-workflows")
+          KARGO_LATEST=$(get_latest_version "akuity/kargo")
+          PACK_LATEST=$(get_latest_version "buildpacks/pack")
+
+          echo "argo=${ARGO_LATEST}" >> "$GITHUB_OUTPUT"
+          echo "kargo=${KARGO_LATEST}" >> "$GITHUB_OUTPUT"
+          echo "pack=${PACK_LATEST}" >> "$GITHUB_OUTPUT"
+
+          ARGO_CURRENT=$(grep -oP 'ARGO_VERSION=\K[0-9.]+' Containerfile)
+          KARGO_CURRENT=$(grep -oP 'KARGO_VERSION=\K[0-9.]+' Containerfile)
+          PACK_CURRENT=$(grep -oP 'PACK_VERSION=\K[0-9.]+' Containerfile)
+
+          echo "argo_current=${ARGO_CURRENT}" >> "$GITHUB_OUTPUT"
+          echo "kargo_current=${KARGO_CURRENT}" >> "$GITHUB_OUTPUT"
+          echo "pack_current=${PACK_CURRENT}" >> "$GITHUB_OUTPUT"
+
+          UPDATES=""
+          if [ "${ARGO_CURRENT}" != "${ARGO_LATEST}" ]; then
+            UPDATES="${UPDATES}- Argo Workflows CLI: ${ARGO_CURRENT} -> ${ARGO_LATEST}\n"
+          fi
+          if [ "${KARGO_CURRENT}" != "${KARGO_LATEST}" ]; then
+            UPDATES="${UPDATES}- Kargo CLI: ${KARGO_CURRENT} -> ${KARGO_LATEST}\n"
+          fi
+          if [ "${PACK_CURRENT}" != "${PACK_LATEST}" ]; then
+            UPDATES="${UPDATES}- pack (Buildpacks): ${PACK_CURRENT} -> ${PACK_LATEST}\n"
+          fi
+
+          if [ -z "${UPDATES}" ]; then
+            echo "has_updates=false" >> "$GITHUB_OUTPUT"
+            echo "No updates found."
+          else
+            echo "has_updates=true" >> "$GITHUB_OUTPUT"
+            # Use a delimiter for multiline output
+            {
+              echo "summary<<EOF"
+              echo -e "${UPDATES}"
+              echo "EOF"
+            } >> "$GITHUB_OUTPUT"
+            echo -e "Updates found:\n${UPDATES}"
+          fi
+
+      - name: Update versions in Containerfile and manifest
+        if: steps.versions.outputs.has_updates == 'true'
+        env:
+          ARGO_LATEST: ${{ steps.versions.outputs.argo }}
+          KARGO_LATEST: ${{ steps.versions.outputs.kargo }}
+          PACK_LATEST: ${{ steps.versions.outputs.pack }}
+          ARGO_CURRENT: ${{ steps.versions.outputs.argo_current }}
+          KARGO_CURRENT: ${{ steps.versions.outputs.kargo_current }}
+          PACK_CURRENT: ${{ steps.versions.outputs.pack_current }}
+        run: |
+          if [ "${ARGO_CURRENT}" != "${ARGO_LATEST}" ]; then
+            sed -i "s/ARGO_VERSION=${ARGO_CURRENT}/ARGO_VERSION=${ARGO_LATEST}/g" Containerfile manifest.yaml
+          fi
+          if [ "${KARGO_CURRENT}" != "${KARGO_LATEST}" ]; then
+            sed -i "s/KARGO_VERSION=${KARGO_CURRENT}/KARGO_VERSION=${KARGO_LATEST}/g" Containerfile manifest.yaml
+          fi
+          if [ "${PACK_CURRENT}" != "${PACK_LATEST}" ]; then
+            sed -i "s/PACK_VERSION=${PACK_CURRENT}/PACK_VERSION=${PACK_LATEST}/g" Containerfile manifest.yaml
+          fi
+
+      - name: Create pull request
+        if: steps.versions.outputs.has_updates == 'true'
+        uses: peter-evans/create-pull-request@v7
+        with:
+          commit-message: "chore: update tool versions"
+          branch: chore/update-tool-versions
+          title: "chore: update tool versions"
+          body: |
+            Automated tool version updates:
+
+            ${{ steps.versions.outputs.summary }}
+          labels: dependencies