feat: codecov override with merge squash hash

.github/actions/codecov-merge-upload/action.yml

@@ -0,0 +1,58 @@
+name: 'Codecov Download and Upload'
+description: 'Download coverage artifacts from previous PR runs and upload to Codecov'
+
+inputs:
+  coverage-path:
+    description: 'Path to coverage files'
+    required: true
+  workflow-paths:
+    description: 'Comma-separated list of workflow paths for artifact lookup (e.g., ".github/workflows/router-ci.yaml,.github/workflows/cli-ci.yaml")'
+    required: true
+  override-commit:
+    description: 'Commit SHA to override in Codecov'
+    required: true
+  merge-commit-sha:
+    description: 'Merge commit SHA to look up the PR and find head SHA'
+    required: false
+    default: ''
+  codecov-token:
+    description: 'Codecov token for uploading'
+    required: true
+  github-token:
+    description: 'GitHub token for artifact operations'
+    required: true
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Find latest successful PR runs for this commit
+      id: find-artifacts
+      shell: bash
+      env:
+        GITHUB_TOKEN: ${{ inputs.github-token }}
+        REPO: ${{ github.repository }}
+        HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        MERGE_COMMIT_SHA: ${{ inputs.merge-commit-sha }}
+        CURRENT_RUN_ID: ${{ github.run_id }}
+        ARTIFACT_NAME_PATTERN: codecov
+        WORKFLOW_PATHS: ${{ inputs.workflow-paths }}
+      run: ./.github/scripts/find-codecov-artifact.sh
+
+    - name: Download coverage artifacts
+      if: steps.find-artifacts.outputs.has_artifacts == 'true'
+      shell: bash
+      env:
+        GITHUB_TOKEN: ${{ inputs.github-token }}
+        REPO: ${{ github.repository }}
+        ARTIFACTS_JSON: ${{ steps.find-artifacts.outputs.artifacts_json }}
+        COVERAGE_PATH: ${{ inputs.coverage-path }}
+      run: ./.github/scripts/download-codecov-artifacts.sh
+
+    - name: Upload results to Codecov
+      if: steps.find-artifacts.outputs.has_artifacts == 'true'
+      uses: codecov/codecov-action@v5
+      with:
+        token: ${{ inputs.codecov-token }}
+        override_commit: ${{ inputs.override-commit }}
+        override_branch: main
+        directory: ${{ inputs.coverage-path }}

.github/actions/codecov-upload-pr/action.yml

@@ -0,0 +1,34 @@
+name: 'Codecov Upload PR'
+description: 'Upload coverage artifacts during PR and send to Codecov'
+
+inputs:
+  artifact-name:
+    description: 'Name of the coverage artifact'
+    required: false
+    default: 'pr-build'
+  coverage-path:
+    description: 'Path to coverage files'
+    required: true
+  retention-days:
+    description: 'Days to retain the artifact'
+    required: false
+    default: '7'
+  codecov-token:
+    description: 'Codecov token for uploading'
+    required: true
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Upload artifact for PR
+      uses: actions/upload-artifact@v4
+      with:
+        overwrite: true
+        name: codecov-pr-build-${{ inputs.artifact-name }}
+        path: ${{ inputs.coverage-path }}
+        retention-days: ${{ inputs.retention-days }}
+
+    - name: Upload results to Codecov
+      uses: codecov/codecov-action@v5
+      with:
+        token: ${{ inputs.codecov-token }}

.github/scripts/download-codecov-artifacts.sh

@@ -0,0 +1,52 @@
+#!/bin/bash
+
+# This script downloads coverage artifacts from GitHub Actions runs.
+#
+# Required environment variables:
+#   GITHUB_TOKEN: Required for GitHub CLI authentication
+#   REPO: GitHub repository (e.g., owner/repo)
+#   ARTIFACTS_JSON: JSON array of artifacts to download (from find-codecov-artifact.sh output)
+#   COVERAGE_PATH: Directory where artifacts should be downloaded
+#
+
+set -e
+
+GITHUB_TOKEN="${GITHUB_TOKEN:?GITHUB_TOKEN environment variable is required}"
+REPO="${REPO:?REPO environment variable is required}"
+ARTIFACTS_JSON="${ARTIFACTS_JSON:?ARTIFACTS_JSON environment variable is required}"
+COVERAGE_PATH="${COVERAGE_PATH:?COVERAGE_PATH environment variable is required}"
+
+echo "Downloading artifacts..."
+
+# Validate JSON before processing
+if ! echo "$ARTIFACTS_JSON" | jq empty 2>/dev/null; then
+  echo "ERROR: Invalid JSON received from artifact discovery step" >&2
+  echo "JSON content (truncated to 500 chars):" >&2
+  echo "$ARTIFACTS_JSON" | head -c 500 >&2
+  echo "" >&2
+  exit 1
+fi
+
+echo "$ARTIFACTS_JSON" | jq -c '.[]' | while read -r artifact; do
+  run_id=$(echo "$artifact" | jq -r '.run_id')
+  artifact_id=$(echo "$artifact" | jq -r '.artifact_id')
+  artifact_name=$(echo "$artifact" | jq -r '.artifact_name')
+
+  echo "Downloading artifact: $artifact_name (ID: $artifact_id) from run: $run_id"
+
+  # Download artifact using GitHub CLI
+  gh run download "$run_id" \
+    --repo "$REPO" \
+    --name "$artifact_name" \
+    --dir "$COVERAGE_PATH/$artifact_name"
+
+  if [ $? -eq 0 ]; then
+    echo "✓ Successfully downloaded $artifact_name"
+  else
+    echo "✗ Failed to download $artifact_name" >&2
+    exit 1
+  fi
+done
+
+echo "All artifacts downloaded successfully"
+