self-review 2026-07-30: auto_term stopword filter, real idle_ms, bounded beginSession

- awareness.el: curiosity auto_term was the raw first word of a WM
  label with no term-quality scoring — observed seeds included What,
  Colon, Prose, Context. Replaced the 7-word genre blocklist whack-a-
  mole with a delimited stopword membership test (function words +
  document-structure words); topical terms pass untouched. Verified
  live: seeds now ReasonEdit, Reasoning-model, Self-review.
- routes.el + awareness.el: idle counter only reset on rare inbox
  synthesis-requests, so idle==pulse always (zero information).
  handle_request now stamps soul.last_activity_ts on every inbound
  HTTP request; heartbeat emits idle_ms = ms since last request
  (-1 until first request of a boot).
- neuron-api.el: beginSession concatenated a depth-2 spread plus the
  unbounded self-hub neighbor dump — multi-MB response, doubled by
  wrapper re-escaping, socket died on every call. Now depth-1 and
  the hub dump dropped (identity loading has its own tool). Verified:
  beginSession returns instead of closing the socket.

neuron-api.el

@@ -170,15 +170,25 @@ fn memory_hide_tombstoned(raw: String, path: String) -> String {
 // Spread-activates from session intent, loads self-root neighbors,
 // surfaces recent InternalStateEvent nodes, returns stats + recent nodes.
 fn handle_api_begin_session(body: String) -> String {
+    // PAYLOAD BOUND (2026-07-30 self-review): this handler was the only
+    // working-set endpoint that concatenated UNBOUNDED engram queries —
+    // a depth-2 spread PLUS the full neighbor dump of the self-identity hub
+    // (highest-fanout node in the graph, ~80KB alone; node JSON carries full
+    // content + embeddings). On the ~12k-node store the assembled response
+    // ran to multiple MB, then roughly doubled through two rounds of JSON
+    // re-escaping in the MCP wrapper — the client saw "socket connection
+    // closed unexpectedly" on every beginSession call. Fix: depth-2 → depth-1
+    // spread, and drop the self-hub dump entirely (identity loading has its
+    // own dedicated tool, inspectGraph; duplicating it here served nothing).
+    // self_neighbors key retained as [] for response-shape compatibility.
     let stats: String = engram_stats_json()
-    let activated: String = engram_activate_json("session start recent memory important", 2)
-    let self_nbrs: String = engram_neighbors_json("kn-efeb4a5b-5aff-4759-8a97-7233099be6ee", 1, "both")
+    let activated: String = engram_activate_json("session start recent memory important", 1)
     let state_events: String = engram_scan_nodes_by_type_json("InternalStateEvent", 5, 0)
     let recent: String = engram_scan_nodes_json(10, 0)
     return "{\"stats\":" + stats
         + ",\"recent\":" + api_or_empty(recent)
         + ",\"activated\":" + api_or_empty(activated)
-        + ",\"self_neighbors\":" + api_or_empty(self_nbrs)
+        + ",\"self_neighbors\":[]"
         + ",\"recent_state_events\":" + api_or_empty(state_events) + "}"
 }