runtime: sync from foundation/el; HEAD method support, plus all uncommitted runtime work from prior sessions

runtime/el_runtime.h

@@ -364,6 +364,19 @@ el_val_t  engram_node(el_val_t content, el_val_t node_type, el_val_t salience);
 el_val_t  engram_node_full(el_val_t content, el_val_t node_type, el_val_t label,
                            el_val_t salience, el_val_t importance, el_val_t confidence,
                            el_val_t tier, el_val_t tags);
+/* Layered consciousness — see el_runtime.c for the layered architecture
+ * design notes (search "Layered consciousness architecture"). The five
+ * canonical layers (safety / core-identity / domain-knowledge / imprint /
+ * suit) are seeded automatically; engram_add_layer extends the registry
+ * with imprint or suit overlays at runtime. Nodes default to layer 1
+ * (core-identity) when created via engram_node / engram_node_full. */
+el_val_t  engram_node_layered(el_val_t content, el_val_t node_type, el_val_t label,
+                              el_val_t salience, el_val_t certainty, el_val_t confidence,
+                              el_val_t status, el_val_t tags, el_val_t layer_id);
+el_val_t  engram_add_layer(el_val_t name, el_val_t priority, el_val_t suppressible,
+                           el_val_t transparent, el_val_t injectable);
+el_val_t  engram_remove_layer(el_val_t layer_id);
+el_val_t  engram_list_layers(void);
 el_val_t  engram_get_node(el_val_t id);
 void      engram_strengthen(el_val_t node_id);
 void      engram_forget(el_val_t node_id);
@@ -375,6 +388,8 @@ el_val_t  engram_edge_between(el_val_t from_id, el_val_t to_id);
 el_val_t  engram_neighbors(el_val_t node_id);
 el_val_t  engram_neighbors_filtered(el_val_t node_id, el_val_t max_depth, el_val_t direction);
 el_val_t  engram_edge_count(void);
+/* Three-pass activation: background fan-out → working-memory promotion →
+ * Layer 0 override. See "Three-pass activation" in el_runtime.c. */
 el_val_t  engram_activate(el_val_t query, el_val_t depth);
 el_val_t  engram_save(el_val_t path);
 el_val_t  engram_load(el_val_t path);
@@ -388,6 +403,12 @@ el_val_t  engram_scan_nodes_json(el_val_t limit, el_val_t offset);
 el_val_t  engram_neighbors_json(el_val_t node_id, el_val_t max_depth, el_val_t direction);
 el_val_t  engram_activate_json(el_val_t query, el_val_t depth);
 el_val_t  engram_stats_json(void);
+el_val_t  engram_list_layers_json(void);
+/* engram_compile_layered_json — produce a prompt-ready text block split
+ * into "[LAYER 0 — STRUCTURAL]" (non-suppressible layers, sacred fire)
+ * and "[ENGRAM CONTEXT]" (standard suppressible layers). Returns "" if
+ * no nodes promoted to working memory. */
+el_val_t  engram_compile_layered_json(el_val_t intent, el_val_t depth);
 
 /* ── LLM (Anthropic API client) ─────────────────────────────────────────────
  * All functions call https://api.anthropic.com/v1/messages with the API key
@@ -476,6 +497,21 @@ el_val_t  pq_hybrid_handshake(el_val_t remote_pub_combined);
 
 el_val_t  sha3_256_hex(el_val_t input);
 
+/* ── AEAD: AES-256-GCM (libcrypto-backed) ───────────────────────────────────
+ * Symmetric authenticated encryption used to wrap envelopes after a KEM
+ * handshake. Caller MUST supply a 32-byte key (64 hex chars) — typically the
+ * Kyber-768 / hybrid shared_secret, optionally normalized via SHA3-256.
+ *
+ * aead_encrypt returns a JSON map {"nonce":"...","ciphertext":"..."} where
+ * ciphertext is the AES-256-GCM output with the 16-byte auth tag appended.
+ * Nonce is a fresh 12-byte CSPRNG draw — callers never pick the nonce, which
+ * structurally rules out the GCM nonce-reuse footgun.
+ *
+ * aead_decrypt returns the plaintext String, or "" on any failure (including
+ * auth-tag mismatch). Callers MUST check for "" before trusting the result. */
+el_val_t  aead_encrypt(el_val_t key_hex, el_val_t plaintext);
+el_val_t  aead_decrypt(el_val_t key_hex, el_val_t nonce_hex, el_val_t ciphertext_hex);
+
 /* ── Native VM builtin aliases (for compiled El source) ─────────────────────
  * These match the El VM's native_* builtins so that El source compiled
  * to C can call the same names without modification.                */
@@ -502,6 +538,16 @@ el_val_t  get(el_val_t list, el_val_t index);      /* el_list_get    */
 el_val_t  map_get(el_val_t map, el_val_t key);     /* el_map_get     */
 el_val_t  map_set(el_val_t map, el_val_t key, el_val_t value); /* el_map_set */
 
+/* ── OTLP/HTTP Observability ─────────────────────────────────────────────── */
+/* See bottom of el_runtime.c for the implementation.
+ * Configured by env vars OTLP_ENDPOINT, OTEL_SERVICE_NAME, OTEL_SERVICE_VERSION.
+ * No-op when OTLP_ENDPOINT is unset. Drop-on-failure semantics. */
+el_val_t emit_log(el_val_t level, el_val_t msg, el_val_t fields_json);
+el_val_t emit_metric(el_val_t name, el_val_t value, el_val_t tags_json);
+el_val_t trace_span_start(el_val_t name);
+el_val_t trace_span_end(el_val_t span_handle);
+el_val_t emit_event(el_val_t name, el_val_t duration_ms);
+
 #ifdef __cplusplus
 }
 #endif