chore(ci): simplify Claude prompt to just invoke /updating skill

Author: jdalton

.github/workflows/weekly-update.yml

@@ -85,28 +85,7 @@ jobs:
           set +e
           claude --print --dangerously-skip-permissions \
             --model sonnet \
-            "$(cat <<'PROMPT'
-          /updating
-
-          <context>
-          You are an automated CI agent in a weekly dependency update workflow.
-          Git is configured with GPG signing. A branch has been created for you.
-          </context>
-
-          <instructions>
-          Update all dependencies to their latest versions.
-          Create one atomic commit per dependency update with a conventional commit message.
-          Leave all changes local — the workflow handles pushing and PR creation.
-          Skip running builds, tests, and type checks — CI runs those separately.
-          </instructions>
-
-          <success_criteria>
-          Each updated dependency has its own commit.
-          The lockfile is consistent with package.json changes.
-          No uncommitted changes remain in the working tree.
-          </success_criteria>
-          PROMPT
-          )" \
+            "/updating" \
             2>&1 | tee claude-output.log
           CLAUDE_EXIT=${PIPESTATUS[0]}
           set -e