Vendor Cordis framework packages as source

cordis 4.0.0-rc.6, plugin-loader, -include, -group, -timer, -hmr,
-logger-console, cosmokit 1.8.1, schemastery 3.18.0 — copied from the
cordis-workspace checkout, flattened under vendor/, original npm names,
private: true. vendor/README.md is the manifest: upstream repos +
commit SHAs, local-modification log, sync procedure.

Local modification: hmr's locale YAML imports and .i18n() call removed
(avoids a runtime YAML import hook we don't vendor).

vendor/cosmokit/src/array.ts

@@ -0,0 +1,42 @@
+import { isNullable } from './misc'
+
+/** Return true when every item in `array2` is present in `array1`. */
+export function contain(array1: readonly any[], array2: readonly any[]) {
+  return array2.every(item => array1.includes(item))
+}
+
+/** Return items that appear in both arrays. */
+export function intersection<T>(array1: readonly T[], array2: readonly T[]) {
+  return array1.filter(item => array2.includes(item))
+}
+
+/** Return items from `array1` that do not appear in `array2`. */
+export function difference<S>(array1: readonly S[], array2: readonly any[]) {
+  return array1.filter(item => !array2.includes(item))
+}
+
+/** Return the set-union of two arrays while preserving first occurrence order. */
+export function union<T>(array1: readonly T[], array2: readonly T[]) {
+  return Array.from(new Set([...array1, ...array2]))
+}
+
+/** Remove duplicate values while preserving first occurrence order. */
+export function deduplicate<T>(array: readonly T[]) {
+  return [...new Set(array)]
+}
+
+/** Remove one item from an array and report whether it was found. */
+export function remove<T>(list: T[], item: T) {
+  const index = list?.indexOf(item)
+  if (index >= 0) {
+    list.splice(index, 1)
+    return true
+  } else {
+    return false
+  }
+}
+
+/** Normalize nullish, scalar, or array input to an array. */
+export function makeArray<T>(source: null | undefined | T | T[]) {
+  return Array.isArray(source) ? source : isNullable(source) ? [] : [source]
+}