refactor: replace CodeMirror with plain textarea in config editors

Replace JsonEditor (CodeMirror) with plain HTML textarea elements in Claude
config editors to maintain consistency with Codex config editors and eliminate
theme conflicts.

Changes:
- Replace JsonEditor with textarea in ClaudeConfigEditor.tsx
- Replace JsonEditor with textarea in CommonConfigEditor.tsx
- Remove unnecessary dark mode detection logic
- Remove wrapper div with border class that caused double borders
- Apply unified border design system (border-border-default)
- Keep JsonEditor in UsageScriptModal for JavaScript code editing

Benefits:
- Eliminates CodeMirror theme conflicts with oneDark
- Simplifies codebase by removing unnecessary abstractions
- Consistent styling across all config input fields
- Automatic theme adaptation via CSS variables

src/components/providers/forms/CommonConfigEditor.tsx

@@ -6,9 +6,6 @@ import {
   DialogTitle,
 } from "@/components/ui/dialog";
 import { Label } from "@/components/ui/label";
-import JsonEditor from "@/components/JsonEditor";
-import { useTheme } from "@/components/theme-provider";
-import { useMemo } from "react";
 
 interface CommonConfigEditorProps {
   value: string;
@@ -36,15 +33,6 @@ export function CommonConfigEditor({
   onModalClose,
 }: CommonConfigEditorProps) {
   const { t } = useTranslation();
-  const { theme } = useTheme();
-
-  const isDarkMode = useMemo(() => {
-    if (theme === "dark") return true;
-    if (theme === "light") return false;
-    return typeof window !== "undefined"
-      ? window.document.documentElement.classList.contains("dark")
-      : false;
-  }, [theme]);
 
   return (
     <>
@@ -60,7 +48,7 @@ export function CommonConfigEditor({
                 id="useCommonConfig"
                 checked={useCommonConfig}
                 onChange={(e) => onCommonConfigToggle(e.target.checked)}
-                className="w-4 h-4 text-blue-500 bg-white dark:bg-gray-800 border-border-default  rounded focus:ring-blue-500 dark:focus:ring-blue-400 focus:ring-2"
+                className="w-4 h-4 text-blue-500 bg-white dark:bg-gray-800 border-border-default rounded focus:ring-blue-500 dark:focus:ring-blue-400 focus:ring-2"
               />
               <span>
                 {t("claudeConfig.writeCommonConfig", {
@@ -86,21 +74,28 @@ export function CommonConfigEditor({
             {commonConfigError}
           </p>
         )}
-        <div className="rounded-md border">
-          <JsonEditor
-            value={value}
-            onChange={onChange}
-            placeholder={`{
+        <textarea
+          id="settingsConfig"
+          value={value}
+          onChange={(e) => onChange(e.target.value)}
+          placeholder={`{
   "env": {
     "ANTHROPIC_BASE_URL": "https://your-api-endpoint.com",
     "ANTHROPIC_AUTH_TOKEN": "your-api-key-here"
   }
 }`}
-            darkMode={isDarkMode}
-            rows={14}
-            showValidation
-          />
-        </div>
+          rows={14}
+          className="w-full px-3 py-2 border border-border-default dark:bg-gray-800 dark:text-gray-100 rounded-lg text-sm font-mono focus:outline-none focus:ring-2 focus:ring-blue-500/20 dark:focus:ring-blue-400/20 focus:border-border-active transition-colors resize-y min-h-[16rem]"
+          autoComplete="off"
+          autoCorrect="off"
+          autoCapitalize="none"
+          spellCheck={false}
+          lang="en"
+          inputMode="text"
+          data-gramm="false"
+          data-gramm_editor="false"
+          data-enable-grammarly="false"
+        />
         <p className="text-xs text-muted-foreground">
           {t("claudeConfig.fullSettingsHint", {
             defaultValue: "请填写完整的 Claude Code 配置",
@@ -126,14 +121,21 @@ export function CommonConfigEditor({
                 defaultValue: "通用配置片段将合并到所有启用它的供应商配置中",
               })}
             </p>
-            <div className="rounded-md border">
-              <JsonEditor
-                value={commonConfigSnippet}
-                onChange={onCommonConfigSnippetChange}
-                darkMode={isDarkMode}
-                rows={12}
-              />
-            </div>
+            <textarea
+              value={commonConfigSnippet}
+              onChange={(e) => onCommonConfigSnippetChange(e.target.value)}
+              rows={12}
+              className="w-full px-3 py-2 border border-border-default dark:bg-gray-800 dark:text-gray-100 rounded-lg text-sm font-mono focus:outline-none focus:ring-2 focus:ring-blue-500/20 dark:focus:ring-blue-400/20 focus:border-border-active transition-colors resize-y min-h-[14rem]"
+              autoComplete="off"
+              autoCorrect="off"
+              autoCapitalize="none"
+              spellCheck={false}
+              lang="en"
+              inputMode="text"
+              data-gramm="false"
+              data-gramm_editor="false"
+              data-enable-grammarly="false"
+            />
             {commonConfigError && (
               <p className="text-sm text-red-500 dark:text-red-400">
                 {commonConfigError}