Feat : Github Actions for keeping up with toolchain

.github/dependabot.yml

@@ -0,0 +1,9 @@
+version: 2  # Specifies the version of the Dependabot configuration file format
+
+updates:
+  # Configuration for dependency updates
+  - package-ecosystem: "github-actions"  # Specifies the ecosystem to check for updates
+    directory: "/"  # Specifies the directory to check for dependencies; "/" means the root directory
+    schedule:
+      # Check for updates to GitHub Actions every month
+      interval: "monthly"

.github/workflows/build.yml

@@ -0,0 +1,74 @@
+name: Compile blueprint
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - '**/*.lean'
+  pull_request:
+    branches:
+      - master
+    paths:
+      - '**/*.lean'
+      - 'lean-toolchain'
+      - 'lakefile.toml'
+      - 'lake-manifest.json'
+  workflow_dispatch: # Allow manual triggering of the workflow from the GitHub Actions interface
+
+# Cancel previous runs if a new commit is pushed to the same PR or branch
+concurrency:
+  group: ${{ github.ref }}  # Group runs by the ref (branch or PR)
+  cancel-in-progress: true  # Cancel any ongoing runs in the same group
+
+# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages and modify PR labels
+permissions:
+  contents: read          # Read access to repository contents
+  pages: write            # Write access to GitHub Pages
+  id-token: write         # Write access to ID tokens
+  issues: write           # Write access to issues
+  pull-requests: write    # Write access to pull requests
+
+jobs:
+  build_project:
+    runs-on: ubuntu-latest
+    name: Build project
+    steps:
+      - name: Add 'awaiting-CI' label
+        if: >
+          github.event_name == 'pull_request'
+        run: |
+          curl --request POST \
+            --url https://api.github.com/repos/${{ github.repository }}/issues/${{ github.event.pull_request.number }}/labels \
+            --header 'authorization: Bearer ${{ secrets.PAT_TOKEN }}' \
+            --header 'Content-Type: application/json' \
+            --data '["awaiting-CI"]'
+
+      - name: Checkout project
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0 # Fetch all history for all branches and tags
+
+      - name: Install elan
+        run: curl https://raw.githubusercontent.com/leanprover/elan/master/elan-init.sh -sSf | sh -s -- -y
+
+      - name: Cache build artifacts
+        uses: actions/cache@v4
+        with:
+          path: |
+            .lake/build
+          key: LakeBuild-${{ runner.os }}-${{ hashFiles('lean-toolchain') }}-${{ hashFiles('lake-manifest.json') }}-${{ github.sha }}
+          restore-keys: LakeBuild-
+
+      - name: Build project
+        run: ~/.elan/bin/lake build
+
+      - name: Remove 'awaiting-CI' label
+        if: >
+          always() &&
+          github.event_name == 'pull_request'
+        run: |
+          curl --request DELETE \
+            --url https://api.github.com/repos/${{ github.repository }}/issues/${{ github.event.pull_request.number }}/labels/awaiting-CI \
+            --header 'authorization: Bearer ${{ secrets.PAT_TOKEN }}' \
+            --header 'Content-Type: application/json'

.github/workflows/toolchain-update.yml

@@ -0,0 +1,22 @@
+name: Update Dependencies
+
+on:
+  schedule:             # Sets a schedule to trigger the workflow
+  - cron: "0 8 */10 * *" # Every 10 days at 08:00 AM UTC (for more info on the cron syntax see https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows#schedule)
+  workflow_dispatch:    # Allows the workflow to be triggered manually via the GitHub interface
+
+jobs:
+  update_lean:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write      # Grants permission to push changes to the repository
+      issues: write        # Grants permission to create or update issues
+      pull-requests: write # Grants permission to create or update pull requests
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+      - name: Update project
+        uses: oliver-butterley/lean-update@v1-alpha
+        with:
+          on_update_succeeds: pr # Create a pull request if the update succeeds
+          on_update_fails: issue # Create an issue if the update fails