feat: house tracker with home worker, alerts and listing map

Collects Pararius rent/buy listings into Postgres via a worker that runs on a
residential connection, sends Discord/ntfy alerts for new listings matching
rules, and shows an admin-only map, market stats and worker log.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013HfF5tnChi8tkCx9svJP6D

README.md

@@ -7,6 +7,12 @@ This is my personal website, including:
 - Blog posts + comments
 - Projects like Animaldex, CatchEmAll
 
+## House tracker
+
+Available at `/projects/house-tracker` (admin only). Listings come from a worker
+that runs at home; setup, settings and the ban-avoidance rules are in
+[docs/house-tracker.md](docs/house-tracker.md).
+
 ## osu! Map Finder
 
 Available at `/projects/spotify-beatmap-finder`. Built with the existing Svelte 5,