ci: publish regtest apk on pr builds

.github/workflows/ci.yml

@@ -21,6 +21,13 @@ jobs:
     if: github.event.pull_request.draft == false
     runs-on: ubuntu-latest
 
+    permissions:
+      contents: read
+      packages: read
+
+    outputs:
+      artifact-url: ${{ steps.upload-apk.outputs.artifact-url }}
+
     steps:
       - name: Checkout
         uses: actions/checkout@v7
@@ -47,6 +54,7 @@ jobs:
           GOOGLE_SERVICES_JSON_BASE64: ${{ secrets.GOOGLE_SERVICES_JSON_BASE64 }}
 
       - name: Build debug app
+        id: build
         env:
           GITHUB_ACTOR: ${{ github.actor }}
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -57,8 +65,56 @@ jobs:
         run: ./gradlew testDevDebugUnitTest
 
       - name: Upload test report
+        if: always() && steps.build.outcome == 'success'
         uses: actions/upload-artifact@v7
         with:
           name: unit_test_report_${{ github.run_number }}
           path: app/build/reports/tests/testDevDebugUnitTest/
           retention-days: 30
+
+      - name: Upload APK
+        id: upload-apk
+        uses: actions/upload-artifact@v7
+        with:
+          name: bitkit-dev-debug-apk_${{ github.run_number }}
+          path: app/build/outputs/bitkit/devDebug/bitkit-dev-debug-*-universal.apk
+          retention-days: 30
+          if-no-files-found: error
+
+  apk-comment:
+    needs: build
+    if: needs.build.outputs.artifact-url != '' && github.event_name == 'pull_request' && github.event.pull_request.head.repo.fork == false
+    runs-on: ubuntu-latest
+
+    permissions:
+      pull-requests: write
+
+    steps:
+      - name: Comment APK link on PR
+        uses: actions/github-script@v8
+        env:
+          ARTIFACT_URL: ${{ needs.build.outputs.artifact-url }}
+          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        with:
+          script: |
+            const marker = '<!-- bitkit-dev-debug-apk -->';
+            const runUrl = `${context.serverUrl}/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId}`;
+            const body = [
+              marker,
+              '### Regtest APK',
+              '',
+              `Built from ${process.env.HEAD_SHA} ([run](${runUrl})).`,
+              '',
+              `[Download bitkit-dev-debug universal APK](${process.env.ARTIFACT_URL}) (expires in 30 days).`,
+            ].join('\n');
+            const comments = await github.paginate(github.rest.issues.listComments, {
+              ...context.repo,
+              issue_number: context.issue.number,
+              per_page: 100,
+            });
+            const existing = comments.find((c) => c.body?.includes(marker));
+            if (existing) {
+              await github.rest.issues.updateComment({ ...context.repo, comment_id: existing.id, body });
+            } else {
+              await github.rest.issues.createComment({ ...context.repo, issue_number: context.issue.number, body });
+            }