chore: one-command deploy to [removed]

The homelab has no rsync, so the tree goes over as a tar stream, and the
destination is wiped first - a stale content-hashed chunk left behind would be
served forever, since /assets/* is cached as immutable.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -56,3 +56,21 @@ IndexedDB, workers, `fetch` and module scripts are all unavailable. The app
 handles this behind two interfaces it never sees through — `PersistenceAdapter`
 (IndexedDB → localStorage → memory) and `SolverHost` (worker → inline) — and
 shows a banner when storage is not durable. Artwork is not carried in that build.
+
+## Deploying
+
+`npm run deploy` builds both targets and publishes to
+**[removed]**.
+
+The homelab has no `rsync`, so the tree goes over as a tar stream, and the
+destination is wiped first: a stale content-hashed chunk left behind would be
+served forever, since `/assets/*` is cached as immutable. Caddy serves
+`/mnt/docker/appdata/caddy/sites/[removed]` as `/srv/[removed]` via a
+read-only bind mount, which is why a deploy needs no container restart — but
+adding a *new* site does, and recreating that container briefly drops every
+other site behind Caddy.
+
+`[removed]` is the single-file offline build, shipped
+alongside the app.
+
+`dist/` is not in git. The deploy builds from source.