[codex] fix cross-database JSON boundary handling (#283)

* fix: normalize cross-database json boundaries

* fix: address json boundary review comments

---------

Co-authored-by: apple <apple@appledeMacBook-Pro.local>

src/server/services/proxyVideoTaskStore.test.ts

@@ -0,0 +1,14 @@
+import { describe, expect, it } from 'vitest';
+import { __proxyVideoTaskStoreTestUtils } from './proxyVideoTaskStore.js';
+
+describe('proxyVideoTaskStore', () => {
+  it('accepts parsed object input for JSON column helpers', () => {
+    expect(__proxyVideoTaskStoreTestUtils.parseJsonColumn({
+      status: 'done',
+      id: 'video-1',
+    })).toEqual({
+      status: 'done',
+      id: 'video-1',
+    });
+  });
+});