Migrate server to ESM

Sorry for the very big commit that may lead to git log issues and merge
conflicts, but it's a major step forward:

 * Server can be faster at startup because imports() are async and we can
   easily lazy import big modules
 * Angular doesn't seem to support ES import (with .js extension), so we
   had to correctly organize peertube into a monorepo:
    * Use yarn workspace feature
    * Use typescript reference projects for dependencies
    * Shared projects have been moved into "packages", each one is now a
      node module (with a dedicated package.json/tsconfig.json)
    * server/tools have been moved into apps/ and is now a dedicated app
      bundled and published on NPM so users don't have to build peertube
      cli tools manually
    * server/tests have been moved into packages/ so we don't compile
      them every time we want to run the server
 * Use isolatedModule option:
   * Had to move from const enum to const
     (https://www.typescriptlang.org/docs/handbook/enums.html#objects-vs-enums)
   * Had to explictely specify "type" imports when used in decorators
 * Prefer tsx (that uses esbuild under the hood) instead of ts-node to
   load typescript files (tests with mocha or scripts):
     * To reduce test complexity as esbuild doesn't support decorator
       metadata, we only test server files that do not import server
       models
     * We still build tests files into js files for a faster CI
 * Remove unmaintained peertube CLI import script
 * Removed some barrels to speed up execution (less imports)

server/server/lib/files-cache/video-storyboards-simple-file-cache.ts

@@ -0,0 +1,53 @@
+import { join } from 'path'
+import { logger } from '@server/helpers/logger.js'
+import { doRequestAndSaveToFile } from '@server/helpers/requests.js'
+import { StoryboardModel } from '@server/models/video/storyboard.js'
+import { FILES_CACHE } from '../../initializers/constants.js'
+import { AbstractSimpleFileCache } from './shared/abstract-simple-file-cache.js'
+
+class VideoStoryboardsSimpleFileCache extends AbstractSimpleFileCache <string> {
+
+  private static instance: VideoStoryboardsSimpleFileCache
+
+  private constructor () {
+    super()
+  }
+
+  static get Instance () {
+    return this.instance || (this.instance = new this())
+  }
+
+  async getFilePathImpl (filename: string) {
+    const storyboard = await StoryboardModel.loadWithVideoByFilename(filename)
+    if (!storyboard) return undefined
+
+    if (storyboard.Video.isOwned()) return { isOwned: true, path: storyboard.getPath() }
+
+    return this.loadRemoteFile(storyboard.filename)
+  }
+
+  // Key is the storyboard filename
+  protected async loadRemoteFile (key: string) {
+    const storyboard = await StoryboardModel.loadWithVideoByFilename(key)
+    if (!storyboard) return undefined
+
+    const destPath = join(FILES_CACHE.STORYBOARDS.DIRECTORY, storyboard.filename)
+    const remoteUrl = storyboard.getOriginFileUrl(storyboard.Video)
+
+    try {
+      await doRequestAndSaveToFile(remoteUrl, destPath)
+
+      logger.debug('Fetched remote storyboard %s to %s.', remoteUrl, destPath)
+
+      return { isOwned: false, path: destPath }
+    } catch (err) {
+      logger.info('Cannot fetch remote storyboard file %s.', remoteUrl, { err })
+
+      return undefined
+    }
+  }
+}
+
+export {
+  VideoStoryboardsSimpleFileCache
+}