chore: set FORCE_COLOR=1 in test env for realistic ANSI output

Tests must exercise the same ANSI code paths users see. Without
FORCE_COLOR, chalk disables all color in non-TTY test environments,
making style bugs invisible to the test suite.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/runtime-tests/integration/components/background-color.test.tsx

@@ -1,19 +1,9 @@
-import chalk from "chalk";
-import { afterEach, beforeEach, expect, test } from "vite-plus/test";
+import { expect, test } from "vite-plus/test";
 import { render } from "@vue-tui/testing";
 import { Box, Text } from "@vue-tui/runtime";
 
 const BG_BLUE = "\x1b[44m";
 
-let prevLevel: typeof chalk.level;
-beforeEach(() => {
-  prevLevel = chalk.level;
-  chalk.level = 1;
-});
-afterEach(() => {
-  chalk.level = prevLevel;
-});
-
 test("Box backgroundColor produces ANSI background codes", async () => {
   const { frames } = await render(
     () => <Box backgroundColor="blue" width={5} height={1} />,

packages/runtime-tests/vite.config.ts

@@ -3,6 +3,10 @@ import vueJsx from "@vitejs/plugin-vue-jsx";
 
 export default defineConfig({
   plugins: [vueJsx()],
+  test: {
+    // chalk disables color in non-TTY envs; force it on so ANSI style bugs don't hide from tests
+    env: { FORCE_COLOR: "1" },
+  },
   lint: {
     options: { typeAware: true, typeCheck: true },
   },