perf(ci): use four ARM test workers and remove repeated compilation (#23685)

* ci: benchmark per-job Node compile caching on full unit shards

* ci: measure unit shards with three and four workers

* ci: benchmark localization extraction CLI patch

* perf(build): reuse identical relay bundles across platforms

* ci: compare Vitest 4 and 5 on complete ARM shards

* perf(ci): upgrade localization extraction to skip irrelevant syntax walks

* perf(ci): use all four ARM cores and remove benchmark workflows

* ci: preserve failures while capturing unit source revision

* fix(ci): preserve commented and escaped localization calls

* ci: remove corrected localization benchmark harness

.github/workflows/unit-tests.yml

@@ -83,9 +83,11 @@ jobs:
           ORCA_BALANCE_UNIT_SHARDS: '1'
           ORCA_BACKGROUND_LAUNCH: '1'
         run: |
-          export ORCA_SHARD_SOURCE_SHA="$(git rev-parse HEAD)"
+          ORCA_SHARD_SOURCE_SHA="$(git rev-parse HEAD)"
+          export ORCA_SHARD_SOURCE_SHA
           pnpm exec vitest run --config config/vitest.config.ts \
-            --shard=${{ matrix.shard.index }}/${{ matrix.shard.count }}
+            --shard=${{ matrix.shard.index }}/${{ matrix.shard.count }} \
+            ${{ inputs.runner == 'ubuntu-24.04-arm' && '--maxWorkers=4' || '' }}
 
       - name: Upload unit shard assignment
         if: always()