ci: add copilot help workflow

Author: stackia

.github/workflows/copilot-help.yaml

@@ -0,0 +1,69 @@
+name: Copilot Help
+
+on:
+  issues:
+    types: [labeled]
+
+jobs:
+  copilot-answer:
+    if: github.event.label.name == 'help wanted'
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      contents: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v5
+
+      - name: Install Copilot CLI
+        run: |
+          curl -fsSL https://gh.io/copilot-install | bash
+          echo "$HOME/.local/bin" >> $GITHUB_PATH
+
+      - name: Generate response with Copilot CLI
+        id: copilot
+        env:
+          GH_TOKEN: ${{ secrets.COPILOT_PAT }}
+        run: |
+          ISSUE_URL="${{ github.event.issue.html_url }}"
+
+          PROMPT="You are an AI assistant bot for the project maintainer, helping to answer user questions and issues.
+
+          Please read the GitHub issue at ${ISSUE_URL} including all comments. Analyze the entire conversation and provide helpful answers to any unresolved questions in the issue thread.
+
+          Your role:
+          - Act as a knowledgeable assistant representing the project maintainer
+          - Provide accurate, helpful, and well-researched answers
+          - Reference the codebase, documentation, and existing solutions when applicable
+          - Be professional, friendly, and supportive
+          - If you're uncertain about something, acknowledge it clearly
+
+          Important instructions:
+          1. Your response must be in the same language as the primary language used in the issue discussion. For example, if the issue is discussed in Chinese, respond in Chinese.
+          2. After your analysis, output your final answer wrapped with special markers:
+             - Start with: === FINAL ANSWER BEGIN ===
+             - End with: === FINAL ANSWER END ===
+          3. The content between these markers should be the clean, well-formatted response to post as a GitHub issue comment."
+
+          copilot -p "$PROMPT" --allow-all-tools --silent > response_raw.md
+
+          # Extract content between markers
+          sed -n '/=== FINAL ANSWER BEGIN ===/,/=== FINAL ANSWER END ===/p' response_raw.md | \
+            sed '1d;$d' > response.md
+
+      - name: Post comment to issue
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          gh issue comment ${{ github.event.issue.number }} \
+            --repo ${{ github.repository }} \
+            --body-file response.md
+
+      - name: Remove help wanted label
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          gh issue edit ${{ github.event.issue.number }} \
+            --repo ${{ github.repository }} \
+            --remove-label "help wanted"