feat(runtime): Vue terminal renderer with Ink-aligned API

Custom Vue 3 renderer for terminal UIs, built on yoga-layout for
flexbox and chalk for styling.

Components: Box, Text, Newline, Spacer, Static, Transform
Composables: useExit, useInput, useFocus, useFocusManager,
  useStdin, useStdout, useStderr, useTerminalSize
Entry: createApp(root) → app.mount(options) → app.waitUntilExit()
Focus: Ink-aligned Tab/Shift+Tab/Escape with Focusable[] ring
Internal subpath: @vue-tui/runtime/internal (yogaNodeTracker)

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

packages/runtime/vite.config.ts

@@ -0,0 +1,15 @@
+import { defineConfig } from "vite-plus";
+import vueJsx from "@vitejs/plugin-vue-jsx";
+
+export default defineConfig({
+  plugins: [vueJsx()],
+  pack: {
+    entry: ["src/index.ts", "src/internal.ts"],
+    dts: { tsgo: true },
+    exports: true,
+  },
+  lint: {
+    options: { typeAware: true, typeCheck: true },
+  },
+  fmt: {},
+});