workflows: add agents.md

.github/workflows/copilot-setup-steps.yml

@@ -14,6 +14,14 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 20
 
+    # Set the permissions to the lowest permissions possible needed for your steps.
+    # Copilot will be given its own token for its operations.
+    permissions:
+      # If you want to clone the repository as part of your setup steps, for example to install dependencies, you'll need the `contents: read` permission. If you don't clone the repository in your setup steps, Copilot will do this for you automatically after the steps complete.
+      contents: write
+      actions: write
+      pull-requests: write
+
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
@@ -33,5 +41,31 @@ jobs:
           add-job-summary-as-pr-comment: on-failure
 
       - name: Run Copilot setup script
+        id: sb
         run: node .github/commands/setupCopilot.js
-        shell: bash
+        shell: bash
+
+      - name: Checkout latest mc code (external repo)
+        # If the external repo is public, the default token is fine.
+        # If it's private, create a personal access token with repo access and add it
+        # to this repo's secrets as EXTRA_REPO_TOKEN.
+        uses: actions/checkout@v4
+        with:
+          repository: extremeheat/extracted_minecraft_data
+          path: mc-source/${{ steps.sb.outputs.latest_version }}
+          ref: client${{ steps.sb.outputs.latest_version }}
+          fetch-depth: 1
+
+      - name: Checkout second latest mc code (external repo)
+        # If the external repo is public, the default token is fine.
+        # If it's private, create a personal access token with repo access and add it
+        # to this repo's secrets as EXTRA_REPO_TOKEN.
+        uses: actions/checkout@v4
+        with:
+          repository: extremeheat/extracted_minecraft_data
+          path: mc-source/${{ steps.sb.outputs.second_latest_version }}
+          ref: client${{ steps.sb.outputs.second_latest_version }}
+          fetch-depth: 1
+
+      - name: Write diff
+        run: cd mc-source && git diff --no-index ${{ steps.sb.outputs.second_latest_version }} ${{ steps.sb.outputs.latest_version }} > ${{ steps.sb.outputs.second_latest_version }}_to_${{ steps.sb.outputs.latest_version }}.diff