feat(primitives): media-editor components, category reorg, perf + type cleanup

Reorganize components into category folders (forms/canvas/overlays/etc.); add the
media-editor headless family (timeline, curve-editor, waveform, crop, color
picker, etc.); apply perf fixes (O(1) collection lookups, plain-object drag
state, gesture-leak teardown, shallowRef color state, rect caching) and replace
source `any` with proper types.

vue/primitives/src/menus/menu/useIsUsingKeyboard.ts

@@ -0,0 +1,23 @@
+import { ref } from 'vue';
+
+const isUsingKeyboard = ref(false);
+let initialized = false;
+
+function init() {
+  if (initialized || typeof document === 'undefined') return;
+  initialized = true;
+  document.addEventListener('keydown', () => {
+    isUsingKeyboard.value = true;
+  }, { capture: true, passive: true });
+  document.addEventListener('pointerdown', () => {
+    isUsingKeyboard.value = false;
+  }, { capture: true, passive: true });
+  document.addEventListener('pointermove', () => {
+    isUsingKeyboard.value = false;
+  }, { capture: true, passive: true });
+}
+
+export function useIsUsingKeyboard() {
+  init();
+  return isUsingKeyboard;
+}