test: migrate test & utils (#14569)

#### PR Dependency Tree


* **PR #14569** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Chores**
* Upgraded development test tooling to Vitest v4 and added Playwright
browser test integration; normalized test configurations and CI shard
matrix.

* **Tests**
* Added a large suite of new integration tests covering editor flows
(edgeless, database, embeds, images, latex, code, clipboard,
multi-editor, presentation, undo/redo, etc.).
* Removed numerous end-to-end Playwright test suites across the same
feature areas.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/framework/store/package.json

@@ -29,7 +29,7 @@
   "devDependencies": {
     "@types/lodash.clonedeep": "^4.5.9",
     "@types/lodash.merge": "^4.6.9",
-    "vitest": "^3.2.4"
+    "vitest": "^4.0.18"
   },
   "exports": {
     ".": "./src/index.ts",