feat: Support importing .docx or .html files as new documents (#1551)

* Support importing .docx as new documents

* Add html file support, build types and interface for easily adding file types to importer

* fix: Upload embedded images in docx to storage

* refactor: Bulk of logic to command

* refactor: Do all importing on server, so we're not splitting logic for import into two places

* test: Add documentImporter tests


Co-authored-by: Lance Whatley <whatl3y@gmail.com>

server/utils/parseImages.js

@@ -0,0 +1,26 @@
+// @flow
+import { parser } from "rich-markdown-editor";
+
+export default function parseImages(text: string): string[] {
+  const value = parser.parse(text);
+  const images = [];
+
+  function findImages(node) {
+    if (node.type.name === "image") {
+      if (!images.includes(node.attrs.src)) {
+        images.push(node.attrs.src);
+      }
+
+      return;
+    }
+
+    if (!node.content.size) {
+      return;
+    }
+
+    node.content.descendants(findImages);
+  }
+
+  findImages(value);
+  return images;
+}