Remove poc-memory daemon and RPC infrastructure

The background daemon and its job orchestration are redundant now that
the consciousness binary handles everything directly. Gut daemon.rs
down to just GraphHealth + compute_graph_health (used by the F4 TUI
screen), remove the DaemonCmd CLI subcommand, strip daemon RPC
fast-paths from cli/agent.rs, and drop the jobkit dependency.

-1330 lines.

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

src/lib.rs

@@ -80,5 +80,5 @@ pub use hippocampus::query::parser as query_parser;
 pub use subconscious as agents;
 pub use subconscious::{
     audit, consolidate,
-    digest, daemon,
+    digest,
 };