feat(soul): memories form connections when written

The design rejects what this system did: promotion must link candidates 'using
typed semantic edges rather than appending as unlinked content' (CCR claim 29).
Unlinked append was the only behaviour we had. Measured 2026-08-09: 14,214 edges
over 80,936 nodes, 5% of nodes connected to anything, and no edge created by any
write since 2026-07-19 across 27,000+ new nodes. A memory with no connections is
unreachable by spreading activation, so retrieval degrades to literal matching.

On write, a memory is now linked to its top related existing memories.

Bounds, each bought with a specific failure:
  - max 3 edges per memory (link_memories.py's cap: precision over spray)
  - never link to identity. The existing policy is explicit that 'memories must
    not pollute the self traversal by similarity; only an explicit citation may
    touch identity'.
  - never link telemetry (state-event, soul-response, boot_count, loop-outcome,
    search-result): ~97% of daily write volume. Linking it would add thousands of
    noise edges a day and re-flatten the graph in the name of connecting it.
  - fail-soft: a failed association never fails the write
  - associate only AFTER durability, so no edge points at a node that did not
    persist — that is the dangling-edge defect the 08-09 cleanup removed 830 of

Two defects found by measuring rather than reading, both fixed here:
  1. Hooking mem_store alone produced ZERO edges across four real writes. The HTTP
     memory route writes via wt_node directly; mem_store serves only the awareness
     telemetry paths we refuse to link.
  2. A lowercase-only identity check let a memory link to 'Self — Values
     (grounded)' — the exact pollution the policy forbids. My verification shared
     the blind spot and printed PASS. Now uses str_lower.

Measured, lab, same corpus: ~1-2 edges per memory; identity edges unchanged at
475; zero identity leaks post-fix including an adversarial batch of six memories
written about values. Edges route through wt_edge so they reach the owner.

Rung: E2E-VERIFIED in an isolated lab. Not deployed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

neuron-api.el

@@ -380,6 +380,13 @@ fn handle_api_remember(body: String) -> String {
         sal, sal, el_from_float(0.9),
         "Episodic", final_tags)
     if !api_persisted(id) { return api_not_persisted(id) }
+    // Associate on write (2026-08-09). THIS CALL MUST BE HERE, not only in mem_store.
+    // The HTTP memory route writes via wt_node directly; mem_store serves only the
+    // awareness paths (soul-response, search-result, activation-result) which are
+    // exactly the telemetry we refuse to link. Hooking mem_store alone produced
+    // ZERO edges across four real writes — measured, not assumed, which is the only
+    // reason it was caught before shipping.
+    mem_associate(id, content, "memory:remembered")
     return "{\"id\":\"" + id + "\",\"ok\":true}"
 }