soul: native cognitive API — port all MCP logic to soul daemon

neuron-api.el is a new first-class El module that implements all Neuron
cognitive API handlers natively — no HTTP round-trips, no MCP wrapper,
direct engram builtin calls. All capabilities that previously lived in
the MCP wrapper adapter now live here in the soul.

Handlers: begin_session, compile_ctx, remember, recall, search_knowledge,
browse_knowledge, capture_knowledge, evolve_knowledge, promote_knowledge,
browse_processes, define_process, log_state_event, list_state_events,
inspect_config, tune_config, inspect_graph, link_entities, list_typed,
consolidate.

Routes wired in routes.el under /api/neuron/* (GET + POST).

Also compiles all loop-1/loop-2 .el source changes into dist/*.c and
rebuilds the binary. memory.elh and neuron-api.elh updated with new exports.

memory.elh

@@ -11,3 +11,6 @@ extern fn mem_forget(node_id: String) -> Void
 extern fn mem_consolidate() -> String
 extern fn mem_save(path: String) -> Void
 extern fn mem_load(path: String) -> Void
+extern fn mem_boot_count_get() -> Int
+extern fn mem_boot_count_inc() -> Int
+extern fn mem_emit_state_event(trigger: String, kind: String, content: String) -> String