cli: convert simple commands to use memory_rpc

Commands now forward to daemon (or fallback to local store):
- query → memory_query
- journal tail → journal_tail
- graph link-set → memory_link_set
- graph link-add → memory_link_add
- weight-set → memory_weight_set
- node rename → memory_rename

Removes ~50 lines of duplicated store access code.

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

src/cli/misc.rs

@@ -203,9 +203,12 @@ pub fn cmd_query(expr: &[String]) -> Result<(), String> {
     }
 
     let query_str = expr.join(" ");
-    let store = crate::store::Store::load()?;
-    let graph = store.build_graph();
-    crate::query_parser::run_query(&store, &graph, &query_str)
+    let result = crate::mcp_server::memory_rpc(
+        "memory_query",
+        serde_json::json!({"query": query_str}),
+    ).map_err(|e| e.to_string())?;
+    print!("{}", result);
+    Ok(())
 }
 
 pub fn get_group_content(group: &crate::config::ContextGroup, store: &crate::store::Store, cfg: &crate::config::Config) -> Vec<(String, String)> {