radar: pass 14 — W7 content/snapshot reimplements persist/snapshot facet on raw KV (delegate nudge); persist/* copies are worktree artifacts not consumers

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

plans/abstractions.md

@@ -12,6 +12,12 @@ Anything short → _Watching_ (what's missing) or _Rejected_ (why).
 
 ## Last scan
 
+- **Date:** 2026-06-07 (radar loop, pass 14)
+- **Pass 14:** filename census flagged `snapshot`×?? — but the `*/lib/persist/snapshot.sx`
+  copies are just the merged `lib/persist` in each worktree, NOT consumers (same artifact
+  as `lib/feed/rank.sx` everywhere). The one distinct file, `content/snapshot.sx`,
+  reimplements persist's projection-checkpoint on raw KV instead of using `persist/snapshot`
+  → new W7 (persist-adoption nudge). `audit`×3 = the W4 fakes (acl/mod/identity), known.
 - **Date:** 2026-06-07 (radar loop, pass 13)
 - **Pass 13 — honest re-test, no gate-clearer.** Re-tested the two longest-waiting gates
   against the maturing app-domain loops: **W2** (per-viewer visibility) still 2 consumers
@@ -272,6 +278,22 @@ Anything short → _Watching_ (what's missing) or _Rejected_ (why).
 
 ---
 
+### W7 · Snapshot/projection-checkpoint reimplemented vs `persist/snapshot` (delegate)
+- `persist/lib/persist/snapshot.sx` already provides a **generic** projection checkpoint:
+  store `{:value :seq}` in the kv facet under a namespaced key; the headline property is
+  **snapshot + tail == full replay** (pure, clock-free).
+- `content/lib/content/snapshot.sx` **reimplements that same pattern on raw persist KV**
+  rather than delegating: `persist/kv-put b (content/-snap-key doc-id) {:doc … :seq seq}`
+  (:20), `persist/kv-has?`/`kv-get` (:27-28), and its own tail-replay (:53-59). It never
+  calls `persist/snapshot-*`. content's doc-materialisation *is* a projection fold over
+  its op stream — exactly what `persist/snapshot` checkpoints generically.
+- **Disposition:** persist-adoption nudge (like W4): content could delegate to
+  `persist/snapshot` (its projection = "fold ops → doc"), dropping the duplicated
+  KV+replay code. Home already exists → NOT an extraction; owned by content × persist
+  loops. Only 1 reinventor today; watch whether commerce/events/identity also hand-roll a
+  snapshot on raw KV instead of using the facet (would strengthen the nudge). NB timeline:
+  unclear if `persist/snapshot` predated content's — flag, don't blame.
+
 ### W6 · Guarded lifecycle state machine (illegal transition = explicit error)
 - Recurs as a **design principle**, NOT a shared structure (found pass 10):
   - `mod/lib/mod/lifecycle.sx` — pure SX: immutable case `{:state :error :history …}`,