[libc] [llvm] [libc][ci] Add automated pre-commit and post-commit coverage bots (PR #215269)

[via llvm-commits]

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@@ -0,0 +1,362 @@
+name: libc pre-commit code coverage
+
+permissions:
+  contents: read
+  pull-requests: write # Required to post/update pre-commit coverage comments
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - pre-commit-bot
+      - main
+    paths:
+      - 'libc/src/**'
+      - 'libc/include/**'
+      - 'libc/test/**'
+      - 'libc/CMakeLists.txt'
+      - '.github/workflows/libc-pre-commit-coverage.yml'
+      - '!libc/docs/**'
+      - '!libc/benchmarks/**'
+      - '!libc/fuzzing/**'
+      - '!libc/utils/**'
+      - '!**.md'
+  pull_request:
+    paths:
+      - 'libc/src/**'
+      - 'libc/include/**'
+      - 'libc/test/**'
+      - 'libc/CMakeLists.txt'
+      - '.github/workflows/libc-pre-commit-coverage.yml'
+      - '!libc/docs/**'
+      - '!libc/benchmarks/**'
+      - '!libc/fuzzing/**'
+      - '!libc/utils/**'
+      - '!**.md'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  pre-commit-coverage:
+    timeout-minutes: 60
+    name: libc-pre-commit-coverage
+    runs-on: ubuntu-24.04
+    container:
+      image: ghcr.io/llvm/libc-ubuntu-24.04:latest at sha256:8fee4c9ce5a1fd095686593cd36e032c48a31b6ae575378c82accd1d86a08d59
+      options: >-
+        --privileged
+    defaults:
+      run:
+        shell: bash
+    steps:
+    - name: Checkout Code
+      uses: actions/checkout at v4
+      with:
+        ref: ${{ github.event.pull_request.head.sha || github.sha }}
+        fetch-depth: 2
+        persist-credentials: false
+
+    - name: Setup Compiler Cache (sccache)
+      uses: hendrikmuhs/ccache-action at v1.2.23
----------------
github-advanced-security[bot] wrote:

## zizmor / 

unpinned action reference: action is not pinned to a hash (required by blanket policy)

[Show more details](https://github.com/llvm/llvm-project/security/code-scanning/2306)

https://github.com/llvm/llvm-project/pull/215269