Lohnt sich dein eigenes Dailygram?

Build me a personal social-profile email digest to replace Dailygram. Requirements:

- Node 22 + Express + better-sqlite3, with a localhost admin page for adding,
  editing, pausing, and deleting monitored profiles.
- Each profile stores network, handle, source URL, and an RSS, Atom, or JSON feed
  URL. Keep one small adapter per feed format and validate each feed when saved.
- Poll enabled feeds every 6 hours with node-cron, normalize posts to one schema,
  and deduplicate by source ID, then canonical URL, before inserting into SQLite.
- Summarize only new posts with the OpenAI SDK: one sentence per post plus a
  five-bullet digest overview. Read OPENAI_API_KEY and model name from .env.
- Send one responsive HTML email per day through Nodemailer and SMTP credentials
  from .env, grouped by profile with timestamps and links to original posts.
- The dashboard shows last poll, next digest, source errors, and a preview of the
  exact pending email. Add a Run now button for polling and another for sending.
- Retry failed fetches and email sends three times with backoff, preserve the error
  message, and never mark a digest sent until SMTP accepts it.
- Bind to localhost only. No accounts, billing, telemetry, or cloud control plane;
  all data stays in SQLite except feed, OpenAI, and SMTP requests.
- Out of scope: logging into or scraping social networks, bypassing rate limits,
  mobile apps, and multi-user collaboration. Do not pretend feeds always exist.
- Include tests for normalization, deduplication, and digest selection, plus a README
  covering setup, .env keys, database backup, and the feed-access limitation.