persist: materialized views — stay current on write, O(1) read + 11 tests

view.sx: persist/view bundles stream + fold + snapshot name; view-attach
subscribes it to a hub so each publish refreshes the snapshot incrementally,
making view-peek an O(1) current read. view-value always folds the tail so it
is never stale. The consumer read-model abstraction (feed indices, audit
rollups, search counters). 122/122.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/persist/conformance.sh

@@ -13,7 +13,7 @@ if [ ! -x "$SX_SERVER" ]; then
   exit 1
 fi
 
-SUITES=(event log kv project subscribe concurrency snapshot compaction durable blob recovery)
+SUITES=(event log kv project subscribe concurrency snapshot compaction durable blob view recovery)
 
 OUT_JSON="lib/persist/scoreboard.json"
 OUT_MD="lib/persist/scoreboard.md"
@@ -37,6 +37,7 @@ run_suite() {
 (load "lib/persist/compaction.sx")
 (load "lib/persist/durable.sx")
 (load "lib/persist/blob.sx")
+(load "lib/persist/view.sx")
 (load "lib/persist/subscribe.sx")
 (load "lib/persist/api.sx")
 (epoch 2)