[fix]: scope build-and-test concurrency by event to avoid cancellations

Release branch commits trigger build-and-test from both the push (release/**) and pull_request events, which shared one concurrency group, so cancel-in-progress made them cancel each other. A cancelled run left the required build-and-test check unsatisfied and blocked the release PR merge. Add github.event_name to the concurrency group so push and PR runs no longer cancel each other; per-event cancellation of superseded runs is preserved.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: sf-tyler-jeong

.github/workflows/build-and-test.yml

@@ -9,7 +9,7 @@ on:
       - main
       - release/**
 concurrency:
-  group: build-and-test-${{ github.head_ref || github.ref_name }}
+  group: build-and-test-${{ github.event_name }}-${{ github.head_ref || github.ref_name }}
   cancel-in-progress: true
 
 jobs: