fix(ci): fix vitest config for v4 and use correct test runner

[koistya]

Problem

Two issues causing CI tests to silently run in the wrong environment:

1. bun test ≠ bun run test — bun test invokes Bun's built-in test runner, not the "test": "vitest" script from package.json. Bun's runner ignores all vitest config (environment, plugins, etc.).

2. vitest.workspace.ts silently ignored — The workspace file was removed in Vitest 4 in favor of test.projects in the root config. With the file ignored, vitest fell back to the root config which had no environment: "happy-dom", so DOM-dependent tests would fail.

Changes

File	Change	Why
ci.yml	bun test → bun run test -- --run	Run vitest (not Bun's runner); --run disables watch mode
vitest.config.ts	Add test.projects: ["apps/*"]	Vitest 4 API for project discovery — each app's vite.config.ts provides its own environment, plugins, etc.
vitest.workspace.ts	Deleted	Deprecated since Vitest 3.2, removed in v4

Before / After

// vitest.config.ts (before)
export default defineConfig({
  cacheDir: "./.cache/vite",
});

// vitest.config.ts (after)
export default defineConfig({
  cacheDir: "./.cache/vite",
  test: {
    projects: ["apps/*"],
  },
});