Convert store and CLI to anyhow::Result for cleaner error handling

Replace Result<_, String> with anyhow::Result throughout:
- hippocampus/store module (persist, ops, types, view, mod)
- CLI modules (admin, agent, graph, journal, node)
- Run trait in main.rs

Use .context() and .with_context() instead of .map_err(|e| format!(...))
patterns. Add bail!() for early error returns.

Add access_local() helper in hippocampus/mod.rs that returns
Result<Arc<Mutex<Store>>> for direct local store access.

Fix store access patterns to properly lock Arc<Mutex<Store>> before
accessing fields in mind/unconscious.rs, mind/mod.rs, subconscious/learn.rs,
and hippocampus/memory.rs.

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

src/hippocampus/mod.rs

@@ -22,7 +22,7 @@ pub mod transcript;
 use std::cell::RefCell;
 use std::path::PathBuf;
 use std::sync::{Arc, OnceLock};
-use anyhow::{Context, Result};
+use anyhow::Result;
 use crate::hippocampus::store::Store;
 
 pub use local::{LinkInfo, JournalEntry};
@@ -79,6 +79,15 @@ pub fn access() -> StoreAccess {
     }
 }
 
+/// Get local store access. Returns error if only RPC available.
+pub fn access_local() -> Result<Arc<crate::Mutex<Store>>> {
+    match access() {
+        StoreAccess::Daemon(arc) => Ok(arc),
+        StoreAccess::Client => anyhow::bail!("direct store access not available via RPC"),
+        StoreAccess::None(err) => anyhow::bail!("{}", err),
+    }
+}
+
 pub fn socket_path() -> PathBuf {
     dirs::home_dir()
         .unwrap_or_default()
@@ -150,24 +159,6 @@ pub fn memory_rpc(tool_name: &str, args: serde_json::Value) -> Result<String> {
     })
 }
 
-// ── Helpers ────────────────────────────────────────────────────
-
-fn get_str<'a>(args: &'a serde_json::Value, name: &'a str) -> Result<&'a str> {
-    args.get(name).and_then(|v| v.as_str()).context(format!("{} is required", name))
-}
-
-fn get_f64(args: &serde_json::Value, name: &str) -> Result<f64> {
-    args.get(name).and_then(|v| v.as_f64()).context(format!("{} is required", name))
-}
-
-/// Get provenance from agent state, or "manual".
-async fn get_provenance(agent: &Option<std::sync::Arc<crate::agent::Agent>>) -> String {
-    match agent {
-        Some(a) => a.state.lock().await.provenance.clone(),
-        None => "manual".to_string(),
-    }
-}
-
 // ── Macro for generating tool wrappers ─────────────────────────
 //
 // memory_tool!(name, mut, arg1: [str], arg2: [Option<bool>])