fix(toml): normalize CJK quotes to prevent parsing errors

Add quote normalization to handle Chinese/fullwidth quotes automatically
converted by IME. This fixes TOML parsing failures when users input
configuration with non-ASCII quotes (" " ' ' etc.).

Changes:
- Add textNormalization utility for quote normalization
- Apply normalization in TOML input handlers (MCP form, Codex config)
- Disable browser auto-correction in Textarea component
- Add defensive normalization in TOML parsing layer

src/components/ui/textarea.tsx

@@ -11,6 +11,10 @@ const Textarea = React.forwardRef<HTMLTextAreaElement, TextareaProps>(
           "flex min-h-[80px] w-full rounded-md border border-border-default bg-background px-3 py-2 text-sm shadow-sm placeholder:text-muted-foreground focus:outline-none focus:ring-2 focus:ring-blue-500/20 dark:focus:ring-blue-400/20 disabled:cursor-not-allowed disabled:opacity-50",
           className,
         )}
+        autoComplete="off"
+        autoCorrect="off"
+        autoCapitalize="none"
+        spellCheck={false}
         ref={ref}
         {...props}
       />