Move RSS persistence out of the daemon blob store and into the webui's
own SQLite DB (feeds, rules, indexers tables; articles + affectedFeeds
held as JSON columns). Remove the now-unused daemon blob store
(set/get_webui_blob, blob_lock, data_dir).
With this, all webui-owned state — accounts, taxonomy, RSS — lives in
the webui DB; the daemon only keeps naut's own data (per-torrent labels
still flow through set_labels for Lua).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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