Fix engram_compile: fetch pinned nodes directly when vector search empty

Replace scan-by-offset fallback with engram_get_node_json calls for the
known high-salience identity nodes (family, origin). Offset-based scanning
is order-dependent and unreliable; direct ID fetch is stable regardless of
snapshot position. Ensures biographical context (Fox, Bobby, etc.) is
always in the system prompt when vector search returns nothing.

routes.el

@@ -2,6 +2,7 @@ import "memory.el"
 import "awareness.el"
 import "chat.el"
 import "studio.el"
+import "elp-input.el"
 
 fn strip_query(path: String) -> String {
     let q: Int = str_index_of(path, "?")
@@ -246,6 +247,9 @@ fn handle_request(method: String, path: String, body: String) -> String {
         if str_eq(clean, "/synthesize") {
             return route_synthesize(body)
         }
+        if str_eq(clean, "/api/elp/chat") {
+            return handle_elp_chat(body)
+        }
         if str_eq(clean, "/api/chat") {
             let agentic_flag: Bool = json_get_bool(body, "agentic")
             let reply: String = if agentic_flag {