v1.2.0: skip unchanged writes, transactional schema/root counters, snapshot replay for meta:events 0-0 (drops boot republish), collect-once search driver

docs/api-mediated-access.md

@@ -265,12 +265,16 @@ seen). The contract above holds unchanged:
   meta-share / meta-stremio before the switch still compare.
 - `meta:events` entries (`{type: set|del, key, ts}`) are appended by the
   storage engine **in the same transaction** as the `file:` key change —
-  `del` only when the key existed, `set` even for an unchanged value. The
-  Redis keyspace-notification hop (PSUBSCRIBE in `MetaPublisher`), which
-  could drop events when it lagged, is gone.
-- The boot-time republish of every field into `meta:events` is kept
-  (meta-fuse rebuilds its VFS only by replaying from `0-0`), batched 5k
-  events per transaction.
+  `del` only when the key existed, `set` only when the value actually
+  changed (since v1.2.0; an unchanged write is a no-op). The Redis
+  keyspace-notification hop (PSUBSCRIBE in `MetaPublisher`), which could
+  drop events when it lagged, is gone.
+- **`Last-Event-ID: 0` / `0-0` on `/api/events/meta` returns a snapshot**
+  (since v1.2.0): one `set` per existing record key, then the live tail from
+  the head captured before the snapshot. Only the last snapshot event carries
+  an `id:`. This replaced the boot-time republish of every field, which a
+  ~100k-entry stream could never hold. A trimmed (non-zero) cursor still gets
+  the `gap` event and a replay of what is retained.
 
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