cli: add memory_history, remove dump-json/edges/lookups

- Add memory_history MCP tool for version history
- Convert cmd_history to use memory_rpc
- Add raw parameter to memory_render for editing
- Remove unused: dump-json, list-edges, lookup-bump, lookups
- Fix render_node path in defs.rs/subconscious.rs

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

src/agent/tools/memory.rs

@@ -116,6 +116,7 @@ async fn dispatch(
         "memory_link_set" => link_set(&args).await,
         "memory_link_add" => link_add(agent, &args).await,
         "memory_delete" => delete(&args).await,
+        "memory_history" => history(&args).await,
         "memory_weight_set" => weight_set(&args).await,
         "memory_rename" => rename(&args).await,
         "memory_supersede" => supersede(agent, &args).await,
@@ -131,7 +132,7 @@ async fn dispatch(
 
 // ── Definitions ────────────────────────────────────────────────
 
-pub fn memory_tools() -> [super::Tool; 13] {
+pub fn memory_tools() -> [super::Tool; 14] {
     use super::Tool;
     [
         Tool { name: "memory_render", description: "Read a memory node's content and links.",
@@ -155,6 +156,9 @@ pub fn memory_tools() -> [super::Tool; 13] {
         Tool { name: "memory_delete", description: "Delete a memory node.",
                parameters_json: r#"{"type":"object","properties":{"key":{"type":"string","description":"Node key"}},"required":["key"]}"#,
                handler: Arc::new(|a, v| Box::pin(async move { dispatch("memory_delete", &a, v).await })) },
+        Tool { name: "memory_history", description: "Show version history for a node.",
+               parameters_json: r#"{"type":"object","properties":{"key":{"type":"string","description":"Node key"},"full":{"type":"boolean","description":"Show full content for each version"}},"required":["key"]}"#,
+               handler: Arc::new(|a, v| Box::pin(async move { dispatch("memory_history", &a, v).await })) },
         Tool { name: "memory_weight_set", description: "Set a node's weight directly (0.01 to 1.0).",
                parameters_json: r#"{"type":"object","properties":{"key":{"type":"string"},"weight":{"type":"number","description":"0.01 to 1.0"}},"required":["key","weight"]}"#,
                handler: Arc::new(|a, v| Box::pin(async move { dispatch("memory_weight_set", &a, v).await })) },
@@ -330,6 +334,61 @@ async fn delete(args: &serde_json::Value) -> Result<String> {
     Ok(format!("deleted {}", resolved))
 }
 
+async fn history(args: &serde_json::Value) -> Result<String> {
+    let key = get_str(args, "key")?;
+    let full = args.get("full").and_then(|v| v.as_bool()).unwrap_or(false);
+
+    let arc = cached_store().await?;
+    let store = arc.lock().await;
+    let key = store.resolve_key(key).unwrap_or_else(|_| key.to_string());
+    drop(store);
+
+    let path = crate::store::nodes_path();
+    if !path.exists() {
+        anyhow::bail!("No node log found");
+    }
+
+    use std::io::BufReader;
+    let file = std::fs::File::open(&path)
+        .map_err(|e| anyhow::anyhow!("open {}: {}", path.display(), e))?;
+    let mut reader = BufReader::new(file);
+
+    let mut versions: Vec<crate::store::Node> = Vec::new();
+    while let Ok(msg) = capnp::serialize::read_message(&mut reader, capnp::message::ReaderOptions::new()) {
+        let log = msg.get_root::<crate::memory_capnp::node_log::Reader>()
+            .map_err(|e| anyhow::anyhow!("read log: {}", e))?;
+        for node_reader in log.get_nodes()
+            .map_err(|e| anyhow::anyhow!("get nodes: {}", e))? {
+            let node = crate::store::Node::from_capnp_migrate(node_reader)
+                .map_err(|e| anyhow::anyhow!("{}", e))?;
+            if node.key == key {
+                versions.push(node);
+            }
+        }
+    }
+
+    if versions.is_empty() {
+        anyhow::bail!("No history found for '{}'", key);
+    }
+
+    let mut out = format!("{} versions of '{}':\n\n", versions.len(), key);
+    for node in &versions {
+        let ts = crate::store::format_datetime(node.timestamp);
+        let deleted = if node.deleted { " DELETED" } else { "" };
+        if full {
+            out.push_str(&format!("=== v{} {} {}{} w={:.3} {}b ===\n",
+                node.version, ts, node.provenance, deleted, node.weight, node.content.len()));
+            out.push_str(&node.content);
+            out.push('\n');
+        } else {
+            let preview = crate::util::first_n_chars(&node.content, 120).replace('\n', "\\n");
+            out.push_str(&format!("v{:<3} {}  {:24} w={:.3}  {}b{}\n     {}\n",
+                node.version, ts, node.provenance, node.weight, node.content.len(), deleted, preview));
+        }
+    }
+    Ok(out)
+}
+
 async fn weight_set(args: &serde_json::Value) -> Result<String> {
     let arc = cached_store().await?;
     let mut store = arc.lock().await;