docs: Scribe retention v4.x status (user declined RCs, 2026-08-29); HA Core 2026.8.3 verified

hosts/hass.windy.lan.md

@@ -342,9 +342,12 @@ deployed 2026-08-18 from `216cc99` (backup
     entities (`scribe_states_written`, `scribe_events_written`, rates, sizes).
   - Verified post-restart 14:23 CST: writer started, `scribe_events_written=1`
     (homeassistant_start), states ~110/min, buffer 3, no scribe log errors.
-- **Scribe 3.8.0 has no retention option** (upstream feature, newer versions
-  only). Retention requires upgrading Scribe first; the DB is a fresh 3.x-schema
-  so an upgrade is safe. Do not expect retention YAML keys to validate on 3.8.0.
+- **Scribe 3.8.0 has no retention option.** Retention ships only in the v4.x line,
+  which as of 2026-08-29 has no stable release (v4.0.0rc1/v4.1.0rc1 are
+  prereleases; user declined RCs — data keeps growing until an upgrade). v4.x is
+  a major rewrite (writer.py largely rewritten, migration.py removed, TimescaleDB
+  extension required): re-read release notes before upgrading. Do not expect
+  retention YAML keys to validate on 3.8.0.
 - Recorder stays external-Postgres with `purge_keep_days: 30` for daily UI
   history; Scribe is the permanent archive.