feat: migrate test runner from Bun to Vitest

- Replace bun:test with Vitest across all 22 test files
- Create @sofa/test package with shared setup and DB test helpers
  - setup.ts: vi.mock for @sofa/db/client, Bun.randomUUIDv7 polyfill
  - db.ts: in-memory SQLite via better-sqlite3, seed helpers
- Add per-project vitest configs (packages/core, apps/web)
- Add root vitest.config.ts with projects and v8 coverage
- Set up @vitest/browser + Playwright for web component tests
- Move validateBackupDatabase from core/backup.ts to @sofa/db/client
- Derive required backup tables from schema instead of hard-coded list
- Update CI workflow with Playwright install and Codecov upload
- Update CLAUDE.md documentation for Vitest

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/generate-openapi-spec.ts

@@ -1,8 +1,5 @@
 import packageJson from "../apps/server/package.json" with { type: "json" };
-import {
-  generateOpenApiSpec,
-  openApiTags,
-} from "../apps/server/src/orpc/openapi-spec";
+import { generateOpenApiSpec, openApiTags } from "../apps/server/src/orpc/openapi-spec";
 
 const spec = await generateOpenApiSpec({
   title: "Sofa API",
@@ -54,9 +51,7 @@ for (const pathItem of Object.values(spec.paths ?? {})) {
     const method = pathItem[key];
     if (!method?.requestBody || !("content" in method.requestBody)) continue;
     const content = method.requestBody.content;
-    const unsupported = Object.keys(content).filter(
-      (type) => !supportedMediaTypes.has(type),
-    );
+    const unsupported = Object.keys(content).filter((type) => !supportedMediaTypes.has(type));
     if (unsupported.length > 0) {
       // Replace unsupported types with a single multipart/form-data entry
       for (const type of unsupported) delete content[type];