[feat] update some feature

sync code of  fastrtc,
add text support through datachannel,
fix safari connect problem
support chat without camera or mic

demo/nextjs_voice_chat/frontend/fastrtc-demo/components/ui/theme-toggle.tsx

@@ -0,0 +1,61 @@
+"use client";
+
+import { useTheme } from "@/components/theme-provider";
+import { cn } from "@/lib/utils";
+import { Moon, Sun } from "lucide-react";
+import { useRef } from "react";
+
+interface ThemeToggleProps {
+  className?: string;
+}
+
+export function ThemeToggle({ className }: ThemeToggleProps) {
+  const { theme } = useTheme();
+  const buttonRef = useRef<HTMLButtonElement>(null);
+
+  const toggleTheme = () => {
+    // Instead of directly changing the theme, dispatch a custom event
+    const newTheme = theme === "light" ? "dark" : "light";
+    
+    // Dispatch custom event with the new theme
+    window.dispatchEvent(
+      new CustomEvent('themeToggleRequest', { 
+        detail: { theme: newTheme } 
+      })
+    );
+  };
+
+  return (
+    <button
+      ref={buttonRef}
+      onClick={toggleTheme}
+      className={cn(
+        "w-10 h-10 rounded-md flex items-center justify-center transition-colors relative overflow-hidden",
+        "bg-black/10 hover:bg-black/20 dark:bg-white/10 dark:hover:bg-white/20",
+        className
+      )}
+      aria-label="Toggle theme"
+    >
+      <div className="relative z-10">
+        {theme === "light" ? (
+          <Moon className="h-5 w-5 text-black/70" />
+        ) : (
+          <Sun className="h-5 w-5 text-white/70" />
+        )}
+      </div>
+      
+      {/* Small inner animation for the button itself */}
+      <div 
+        className={cn(
+          "absolute inset-0 transition-transform duration-500",
+          theme === "light" 
+            ? "bg-gradient-to-br from-blue-500/20 to-purple-500/20 translate-y-full" 
+            : "bg-gradient-to-br from-amber-500/20 to-orange-500/20 -translate-y-full"
+        )}
+        style={{
+          transitionTimingFunction: "cubic-bezier(0.22, 1, 0.36, 1)"
+        }}
+      />
+    </button>
+  );
+}