chore(test): bump FORCE_COLOR to 3 for truecolor support

Ink tests use chalk level 3 (24-bit) for hex/rgb/ansi256 colors.
Level 1 (basic 16-color) caused different ANSI codes than expected.

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

packages/runtime-tests/vite.config.ts

@@ -5,7 +5,7 @@ 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" },
+    env: { FORCE_COLOR: "3" },
   },
   lint: {
     options: { typeAware: true, typeCheck: true },