ci: add issue triage and stale-issue automation (#4829)

* ci: add issue triage and stale-issue automation

Adds two GitHub Actions workflows:
- issue-triage.yml: on new issues, runs Claude Code Action to check
  completeness against issue templates and surface similar existing
  issues (open or closed). Labels incomplete issues with 'needs-info'.
- stale-issues.yml: daily cron that closes issues labelled 'needs-info'
  after 48 hours of inactivity.

Refs #4804

* ci: use existing 'issue needs work' label and match repo conventions

- Switch triage/stale workflows from creating a new 'needs-info' label
  to using the existing 'issue needs work' label
- Drop the label-create step and the corresponding allowed-tool entry
- Rename stale workflow to match the new label
- Use ${{ github.token }} for GH_TOKEN to match claude.yml
- Add local-time comment on the cron schedule, matching the style
  used in dependabot-rotation.yml

* ci: address code review feedback on triage and stale workflows

- Add timeout-minutes: 10 to triage job to cap runaway LLM usage
- Add exempt-all-assignees: true so maintainer-claimed issues are
  not auto-closed
- Set stale-issue-message: '' explicitly to document intent
- Drop redundant stale-issue-label (same as only-labels)

* ci: drop unused gh api allowance from triage workflow

Addresses review feedback: gh api:* was broader than needed and
not used by the prompt. The remaining gh issue/search subcommands
cover all documented operations.

* ci: address remaining review feedback on triage and stale workflows

- restore stale-issue-label to prevent default "Stale" label
- correct "48 hours" wording to "2 days" (cron window is up to 72h)
- include generic-issue template placeholders in compliance check
- skip triage for bot-opened issues
- tighten gh search allowlist to gh search issues

* ci: extend needs-info window from 2 to 3 days

Author: pomfrida

.github/workflows/issue-triage.yml

@@ -0,0 +1,98 @@
+name: Issue triage
+
+on:
+  issues:
+    types: [opened]
+  workflow_dispatch:
+    inputs:
+      issue_number:
+        description: 'Issue number to triage (for manual testing)'
+        required: true
+        type: string
+
+jobs:
+  triage:
+    if: github.event_name == 'workflow_dispatch' || github.event.sender.type != 'Bot'
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    permissions:
+      contents: read
+      issues: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 1
+
+      - name: Triage with Claude
+        uses: anthropics/claude-code-action@v1
+        env:
+          GH_TOKEN: ${{ github.token }}
+        with:
+          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
+          prompt: |
+            You are triaging a newly opened issue in the Equinor Design System (EDS) repository.
+
+            Repository: ${{ github.repository }}
+            Issue number: ${{ github.event.issue.number || inputs.issue_number }}
+
+            Start by reading the issue:
+              gh issue view ${{ github.event.issue.number || inputs.issue_number }}
+
+            Do TWO things, in order.
+
+            === 1. Compliance check ===
+            The repo uses issue templates (bug, feature request, generic). Each template has placeholder prompts like:
+              "A clear and concise description of what the bug is."
+              "Steps to reproduce the bug: 1. 2. 3. 4."
+              "Describe the solution you'd like"
+              "In order to <achieve some value>, as a <type of user>, I want <some functionality>." (default generic title)
+              "A clear and concise description of the main goal" (generic: General objective)
+              "(A list of) actionable goals that leads to fulfilling the general objective" (generic: Specific objectives)
+              "The definition of done" (generic: Outcome)
+            Treat the issue as INCOMPLETE if any of the following are true:
+              - Placeholder text is left unchanged
+              - Required sections are empty
+              - The content is too vague or trivial to act on (e.g. only a title with no body, or body is "it doesn't work")
+
+            If INCOMPLETE:
+              a. Add the "issue needs work" label (note: the label name contains spaces, quote it):
+                   gh issue edit ${{ github.event.issue.number || inputs.issue_number }} --add-label "issue needs work"
+              b. Post a single comment (gh issue comment) that:
+                   - Politely thanks the author for opening the issue
+                   - Lists specifically what information is missing
+                   - Notes that the issue will be closed automatically after 3 days if not updated
+                   - Invites the author to edit the issue or add a comment with the missing details
+
+            If COMPLETE: skip this part entirely. Do nothing.
+
+            === 2. Similarity search ===
+            Search for related issues in BOTH open and closed state — a closed issue may contain the resolution.
+
+            Derive 2-4 keyword searches from the issue title and body, then run them:
+              gh search issues --repo ${{ github.repository }} --state all --limit 20 <keywords>
+            You may also use:
+              gh issue list --repo ${{ github.repository }} --state all --search "<keywords>" --limit 20
+
+            Exclude the current issue (#${{ github.event.issue.number || inputs.issue_number }}) from results.
+
+            Apply a HIGH threshold for "related": the issue must clearly overlap in symptom, component, or feature — not just share a common word. Prefer quality over quantity. If unsure, do not comment.
+
+            If you find 1-5 strong matches, post a SINGLE comment that:
+              - Starts with a brief sentence explaining these may be related
+              - Lists each match as: "- #NUMBER — TITLE (open/closed): one-sentence reason it's relevant"
+              - For closed matches with a resolution, call it out explicitly (e.g. "closed as fixed in #XYZ")
+              - Ends with this disclaimer (exact text):
+                _This comment was generated by an LLM and may be inaccurate. Please verify that the linked issues are actually relevant._
+
+            If there are no strong matches: do not post a comment.
+
+            === Constraints ===
+            - Do not modify any files in the repository.
+            - Do not open pull requests.
+            - Post at most one compliance comment and at most one similarity comment.
+            - Keep comments concise and friendly.
+
+          claude_args: >-
+            --allowed-tools
+            "Bash(gh issue view:*),Bash(gh issue list:*),Bash(gh issue edit:*),Bash(gh issue comment:*),Bash(gh search issues:*)"

.github/workflows/stale-issues.yml

@@ -0,0 +1,31 @@
+name: Close stale issues
+
+on:
+  schedule:
+    # Every day at 08:00 Oslo (CEST) / 07:00 Oslo (CET) — 06:00 UTC
+    - cron: '0 6 * * *'
+  workflow_dispatch:
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+    steps:
+      - uses: actions/stale@v9
+        with:
+          only-labels: 'issue needs work'
+          days-before-issue-stale: 3
+          days-before-issue-close: 0
+          remove-issue-stale-when-updated: true
+          exempt-all-assignees: true
+          # Same as only-labels — keeps the existing label in place rather than adding the default "Stale"
+          stale-issue-label: 'issue needs work'
+          stale-issue-message: ''
+          close-issue-message: |
+            Closing this issue because the requested information was not provided within 3 days.
+
+            If you'd like to continue, please reopen the issue and add the missing details (or comment here and a maintainer can reopen it for you).
+          # PRs are not handled by this workflow
+          days-before-pr-stale: -1
+          days-before-pr-close: -1