feat(portal-shell): clean widget design tokens and fix lint:tokens (P1-6)

516 mechanical replacements across 25 widget files:
- spacing xs/sm/md/lg/xl to numeric 1/2/3/4/6
- text-heading-3 to text-lg font-semibold
- bg-danger to bg-destructive
- border border dedup

Fix .eslintrc.tokens.js to use typescript-eslint parser (was importing
uninstalled @typescript-eslint/parser). lint:tokens now passes.

apps/portal-shell/.eslintrc.tokens.js

@@ -2,16 +2,17 @@
  * ESLint Design Tokens 配置（独立运行：eslint -c .eslintrc.tokens.js src）
  *
  * 与 eslint.config.js 中的 design-tokens 规则等价，保留以对齐 teacher-portal 习惯。
+ * 使用 typescript-eslint 包的 parser（与 eslint.config.js 一致）。
  * 关联：project_rules §3.10
  */
-import tsParser from "@typescript-eslint/parser";
+import tseslint from "typescript-eslint";
 
 /** @type {import('eslint').Linter.Config[]} */
-export default [
+export default tseslint.config(
   {
     files: ["**/*.{ts,tsx,js,jsx}"],
     languageOptions: {
-      parser: tsParser,
+      parser: tseslint.parser,
       ecmaVersion: 2024,
       sourceType: "module",
       parserOptions: {
@@ -40,4 +41,4 @@ export default [
       "no-restricted-syntax": "off",
     },
   },
-];
+);