fix: 用 Pointer Events 替代 touch+mouse 事件，修复移动端双触发导致按钮卡死

- pointerdown/pointerup/pointerleave/pointercancel 统一处理所有输入
- 移除分离的 touchstart/touchend/mousedown/mouseup 事件绑定
- WS 断连时清理 pendingStart 状态，防止按钮永久卡死
- 添加 contextmenu 阻止长按弹出菜单

web/app.ts

@@ -133,6 +133,12 @@ function connectWS(): void {
 		state.ws = null;
 		micBtn.disabled = true;
 		if (state.recording) stopRecording();
+		// Clean up pending async start on disconnect
+		if (state.pendingStart) {
+			state.pendingStart = false;
+			state.startCancelled = true;
+			micBtn.classList.remove("recording");
+		}
 		setStatus("disconnected", "已断开");
 		scheduleReconnect();
 	};
@@ -357,40 +363,24 @@ function escapeHtml(s: string): string {
 }
 // ── Event bindings ──
 function bindMicButton(): void {
-	// Touch events (mobile primary)
-	micBtn.addEventListener(
-		"touchstart",
-		(e: TouchEvent) => {
-			e.preventDefault();
-			startRecording();
-		},
-		{ passive: false },
-	);
-	micBtn.addEventListener(
-		"touchend",
-		(e: TouchEvent) => {
-			e.preventDefault();
-			stopRecording();
-		},
-		{ passive: false },
-	);
-	micBtn.addEventListener(
-		"touchcancel",
-		(e: TouchEvent) => {
-			e.preventDefault();
-			stopRecording();
-		},
-		{ passive: false },
-	);
-	// Mouse fallback (desktop testing)
-	micBtn.addEventListener("mousedown", (e: MouseEvent) => {
+	// Pointer Events: unified touch + mouse, no double-trigger
+	micBtn.addEventListener("pointerdown", (e: PointerEvent) => {
 		if (e.button !== 0) return;
+		e.preventDefault();
 		startRecording();
 	});
-	micBtn.addEventListener("mouseup", () => stopRecording());
-	micBtn.addEventListener("mouseleave", () => {
-		if (state.recording) stopRecording();
+	micBtn.addEventListener("pointerup", (e: PointerEvent) => {
+		e.preventDefault();
+		stopRecording();
 	});
+	micBtn.addEventListener("pointerleave", () => {
+		if (state.recording || state.pendingStart) stopRecording();
+	});
+	micBtn.addEventListener("pointercancel", () => {
+		if (state.recording || state.pendingStart) stopRecording();
+	});
+	// Prevent context menu on long press
+	micBtn.addEventListener("contextmenu", (e) => e.preventDefault());
 }
 // ── Init ──
 function init(): void {