✨ Add useHasPrimaryTouch hook to detect primary touch capability

src/hooks/use-has-primary-touch.ts

@@ -0,0 +1,31 @@
+import { browser } from "$app/environment";
+import { writable } from "svelte/store";
+
+export function useHasPrimaryTouch() {
+  const { subscribe, set } = writable(false);
+  if (!browser) {
+    return {
+      subscribe,
+      destroy: () => {},
+    };
+  }
+  const controller = new AbortController();
+  const { signal } = controller;
+
+  const handleTouch = () => {
+    const hasTouch = "ontouchstart" in window || navigator.maxTouchPoints > 0;
+    const prefersTouch = window.matchMedia("(pointer: coarse)").matches;
+    set(hasTouch && prefersTouch);
+  };
+
+  const mq = window.matchMedia("(pointer: coarse)");
+  mq.addEventListener("change", handleTouch, { signal });
+  window.addEventListener("pointerdown", handleTouch, { signal });
+
+  handleTouch();
+
+  return {
+    subscribe,
+    destroy: () => controller.abort(),
+  };
+}