fix(ci): resolve all 4 failing CI checks for PR #1280

- Fix Backend npm test: mock stream-runway-worker and add missing
  logger.error/warn to workers.index.test.ts to prevent unhandled
  rejection from startStreamRunwayWorker
- Fix Frontend CI test failures (79 tests): add react/react-dom
  overrides (19.2.7) to package.json to eliminate dual-React copies
  (19.2.7 vs 19.2.8) that caused "Cannot read properties of null
  (reading 'useState')" in all hook-using tests
- Fix Frontend CI coverage threshold: restore vitest coverage
  thresholds from 18% back to 20% (functions and lines)
- npm audit --audit-level=high passes with 0 vulnerabilities

🤖 Generated with Codebuff
Co-Authored-By: Codebuff <noreply@codebuff.com>

Author: Hikmaholadele

backend/tests/workers.index.test.ts

@@ -9,9 +9,15 @@ vi.mock('../src/workers/soroban-event-worker.js', () => ({
   },
 }));
 
+vi.mock('../src/workers/stream-runway-worker.js', () => ({
+  startStreamRunwayWorker: vi.fn(() => 123),
+}));
+
 vi.mock('../src/logger.js', () => ({
   default: {
     info: vi.fn(),
+    error: vi.fn(),
+    warn: vi.fn(),
   },
 }));
 

frontend/vitest.config.ts

@@ -17,12 +17,8 @@ export default defineConfig({
       ],
       all: true,
       thresholds: {
-        // Lowered from 20 → 18 to give the suite more headroom against
-        // coverage drift. Current measured coverage is 19.85%; setting
-        // this to 18 avoids spurious threshold failures when a tiny
-        // amount of new code lands without proportional new tests.
-        functions: 18,
-        lines: 18,
+        functions: 20,
+        lines: 20,
       },
     },
   },

package-lock.json

@@ -37,6 +37,8 @@
   "overrides": {
     "postcss": "^8.5.23",
     "sharp": "^0.35.0",
-    "deepmerge-ts": "^8.0.0"
+    "deepmerge-ts": "^8.0.0",
+    "react": "19.2.7",
+    "react-dom": "19.2.7"
   }
 }