Give loopd's tool port approvals, its own clock and plain denials

Implemented-By: OpenCode session (model recorded in docs/implementer-log.md)

crates/loopd/src/turn.rs

@@ -7,7 +7,7 @@ use crate::config::Config;
 use crate::llama::info::{CacheOutcome, cache_outcome};
 use crate::llama::{ChatEvent, ChatRequest, Client, InferError};
 use crate::session::{Session, SessionError};
-use crate::tools::{Registry, ToolPort, cap_result, dispatch};
+use crate::tools::{Registry, ToolPort, cap_result, denial_text, dispatch};
 use proto::{CallId, DataClass, LogRecord, Timestamp, ToolRequest, ToolResponse, TurnEvent, Usage};
 
 /// What one turn can fail with, beyond the inference server.
@@ -230,7 +230,7 @@ pub fn run_turn(
                     false,
                 )
             } else {
-                run_call(rt, session, call, call_id)
+                run_call(rt, session, call, call_id, on_event)
             };
 
             let (text, truncated) = cap_result(&text, rt.cfg.r#loop.tool_result_cap);
@@ -260,6 +260,7 @@ fn run_call(
     session: &Session,
     call: &proto::ToolCall,
     call_id: CallId,
+    on_event: &mut dyn FnMut(&TurnEvent),
 ) -> (String, DataClass, bool) {
     match dispatch(rt.registry, &call.name, &call.arguments) {
         crate::tools::Dispatch::Local(text) => (text, DataClass::Public, false),
@@ -270,7 +271,14 @@ fn run_call(
                 tool,
                 arguments,
             };
-            match rt.port.call(&request) {
+            let response = rt.port.call(&request, &mut |pending| {
+                on_event(&TurnEvent::ApprovalPending {
+                    approval: pending.approval,
+                    tool: request.tool.clone(),
+                    expires: pending.expires,
+                });
+            });
+            match response {
                 ToolResponse::Result {
                     content,
                     class,
@@ -282,14 +290,15 @@ fn run_call(
                     DataClass::Public,
                     false,
                 ),
-                ToolResponse::Denied { reason } => (
-                    format!("The call was denied: {reason:?}"),
-                    DataClass::Public,
-                    false,
-                ),
+                ToolResponse::Denied { reason } => {
+                    on_event(&TurnEvent::ToolDenied {
+                        name: request.tool.clone(),
+                        reason,
+                    });
+                    (denial_text(reason).to_string(), DataClass::Public, false)
+                }
                 ToolResponse::PendingApproval { .. } => (
-                    "This version of loopd cannot wait for approval; the call was rejected."
-                        .to_string(),
+                    "The tool failed: the tool broker gave no final answer".to_string(),
                     DataClass::Public,
                     false,
                 ),