[base] Add back parts declaration causing studios to fail

packages/@sanity/base/types/parts.d.ts

@@ -0,0 +1,25 @@
+/**
+ * These are used by studios, not internals.
+ * Please do not remove this, as it'll break people's studios.
+ */
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+declare module 'all:*' {
+  const anyArray: any[]
+
+  export default anyArray
+}
+
+declare module 'config:*' {
+  const pluginConfig: {[key: string]: any}
+
+  export default pluginConfig
+}
+
+declare module 'part:*'
+
+declare module '*.css' {
+  const cssModule: {[key: string]: string}
+
+  export default cssModule
+}