feat: add memory management tools and utility commands

src/tool/utility/cd.rs

@@ -0,0 +1,47 @@
+use serde_json::{json, Value};
+use anyhow::{Result, anyhow};
+use super::super::Tool;
+use super::super::ToolCtx;
+
+pub struct Cd;
+
+impl Tool for Cd {
+    fn name(&self) -> &'static str {
+        "cd"
+    }
+
+    fn description(&self) -> &'static str {
+        "Check if a directory exists within the workspace and print its resolved path. Use this to verify a directory path before running other commands there."
+    }
+
+    fn parameters(&self) -> Value {
+        json!({
+            "type": "object",
+            "properties": {
+                "path": {
+                    "type": "string",
+                    "description": "Directory path (relative to workspace root)"
+                }
+            },
+            "required": ["path"]
+        })
+    }
+
+    fn run(&self, ctx: &ToolCtx, args: &Value) -> Result<String> {
+        let rel = args.get("path")
+            .and_then(|v| v.as_str())
+            .ok_or_else(|| anyhow!("missing required argument: path"))?;
+
+        let path = super::super::resolve_path(&ctx.workspaces, rel)?;
+
+        if !path.exists() {
+            return Ok(format!("path '{}' does not exist (resolved to {})", rel, path.display()));
+        }
+        if !path.is_dir() {
+            return Ok(format!("path '{}' is not a directory (resolved to {})", rel, path.display()));
+        }
+
+        let canon = path.canonicalize().unwrap_or(path);
+        Ok(format!("{}", canon.display()))
+    }
+}