Add Nuggets host upload portal with Seafile integration; v2.0.4

- New /host-upload page: per-host login (username + password) with
  session cookie, drag-and-drop file upload to Seafile via server proxy
- Two upload targets: Episode Upload (audio) and Episode Info (docs)
- Server route: /api/nuggets-upload/* for host auth + file proxy,
  /api/admin/nuggets-upload/hosts for admin CRUD (create/disable/reset pw/delete)
- Admin panel: Nuggets → Upload Portal view to manage host accounts
- Seafile config via SEAFILE_URL / SEAFILE_TOKEN / SEAFILE_NUGGETS_REPO_ID env vars
- Directories default to /Episode Upload and /Episode Info (configurable)
- Uses multer for multipart uploads; 500 MB per-file limit

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server.js

@@ -63,6 +63,7 @@ import { register as registerAnalytics } from './server/routes/analytics.js'
 import { register as registerDownloads } from './server/routes/downloads.js'
 import { register as registerEpisodes } from './server/routes/episodes.js'
 import { register as registerNuggets } from './server/routes/nuggets.js'
+import { register as registerNuggetsHostUpload } from './server/routes/nuggets-host-upload.js'
 import { register as registerFeed } from './server/routes/feed.js'
 import { register as registerQrCodes } from './server/routes/qr-codes.js'
 import { register as registerBiblePassage } from './server/routes/bible-passage.js'
@@ -112,6 +113,7 @@ registerAnalytics(app)
 registerDownloads(app)
 registerEpisodes(app)
 registerNuggets(app)
+registerNuggetsHostUpload(app)
 registerFeed(app)
 registerQrCodes(app)
 registerBiblePassage(app)