perf(agent): stabilkan async & parallel — satu runtime, bounded concurrency, isolasi error

Seperti Claude Code: satu runtime shared, concurrency dibatasi, error
subagent terisolasi (satu node gagal tidak menggagalkan cycle).

- feat(runtime): global tokio runtime via OnceLock — ganti 9+ titik
  Runtime::new() per tool call (spawn, parallel_delegate, workflow,
  explore, dir_cache, daemon handler). Hemat resource, hilangkan panic
  path Runtime::new().expect() di daemon compaction.
- fix(workflow): execute_cycle ganti try_join_all (fail-fast) →
  buffer_unordered(8) + isolasi error per node; node gagal di-log dan
  diganti [ERROR], hasil node lain tetap dipakai (Claude Code-style).
- fix(parallel_delegate): spawn subagent dibatasi per batch max_parallel
  (tidak unbounded threads).
- perf(subagent): run_agent adaptif max_tokens (800/1600/4096), temp 0.2,
  truncate tool output 12k, error-recovery note utk tool error berulang.
- test: runtime singleton + block_on (2 test).

apps/infrastructure/src/tools/parallel_delegate.rs

@@ -123,7 +123,7 @@ impl Tool for ParallelDelegate {
                 .collect()
         } else {
             // Auto-split using LLM
-            let rt = tokio::runtime::Runtime::new()?;
+            let rt = crate::runtime::runtime();
             let directives = rt.block_on(auto_split_task(
                 &task,
                 max_parallel,
@@ -146,49 +146,53 @@ impl Tool for ParallelDelegate {
             "parallel delegation: starting subagents"
         );
 
-        // Spawn agents in parallel
-        let mut handles = Vec::new();
-        for (i, (directive, access)) in directives.iter().enumerate() {
-            let subagent_ctx = SubagentContext::new(
-                directive.clone(),
-                ctx.clone(),
-                format!("{access:?}"),
-                base_url.clone(),
-                api_key.clone(),
-                model.clone(),
-            );
-
-            debug!(agent_index = i, access = ?access, "spawning parallel agent");
-            let handle = spawn_subagent(subagent_ctx, directive.clone(), *access, ctx.clone());
-            handles.push((i, handle));
-        }
-
-        // Join all results
+        // Spawn agents in parallel — bounded: never more than `max_parallel`
+        // subagent threads in flight at once (Claude Code-style isolation).
         let mut results: Vec<(usize, String, String)> = Vec::new();
-        for (i, handle) in handles {
-            match handle.join() {
-                Ok(Ok(output)) => {
-                    info!(agent_index = i, "parallel agent completed");
-                    results.push((i, directives[i].0.clone(), output));
-                }
-                Ok(Err(e)) => {
-                    warn!(agent_index = i, error = %e, "parallel agent failed");
-                    results.push((i, directives[i].0.clone(), format!("[ERROR] {e}")));
-                }
-                Err(e) => {
-                    warn!(agent_index = i, error = ?e, "parallel agent panicked");
-                    results.push((
-                        i,
-                        directives[i].0.clone(),
-                        "[ERROR] Agent panicked".to_string(),
-                    ));
+        for batch in directives.chunks(max_parallel) {
+            let mut handles = Vec::with_capacity(batch.len());
+            for (i, (directive, access)) in batch.iter().enumerate() {
+                let global_idx = results.len() + i;
+                let subagent_ctx = SubagentContext::new(
+                    directive.clone(),
+                    ctx.clone(),
+                    format!("{access:?}"),
+                    base_url.clone(),
+                    api_key.clone(),
+                    model.clone(),
+                );
+
+                debug!(agent_index = global_idx, access = ?access, "spawning parallel agent");
+                let handle = spawn_subagent(subagent_ctx, directive.clone(), *access, ctx.clone());
+                handles.push((global_idx, handle));
+            }
+
+            // Join this batch before spawning the next.
+            for (i, handle) in handles {
+                match handle.join() {
+                    Ok(Ok(output)) => {
+                        info!(agent_index = i, "parallel agent completed");
+                        results.push((i, directives[i].0.clone(), output));
+                    }
+                    Ok(Err(e)) => {
+                        warn!(agent_index = i, error = %e, "parallel agent failed");
+                        results.push((i, directives[i].0.clone(), format!("[ERROR] {e}")));
+                    }
+                    Err(e) => {
+                        warn!(agent_index = i, error = ?e, "parallel agent panicked");
+                        results.push((
+                            i,
+                            directives[i].0.clone(),
+                            "[ERROR] Agent panicked".to_string(),
+                        ));
+                    }
                 }
             }
         }
 
         // Consolidate results
         if synthesize && results.len() > 1 {
-            let rt = tokio::runtime::Runtime::new()?;
+            let rt = crate::runtime::runtime();
             let consolidated =
                 rt.block_on(consolidate_results(&results, &base_url, &api_key, &model))?;
             Ok(format!(

apps/infrastructure/src/tools/utility/dir_cache_update.rs

@@ -63,7 +63,7 @@ impl crate::tools::Tool for DirCacheUpdate {
         // Persist the resolved paths into the shared DirCache so the TUI
         // and other tools can read the cached listing without re-scanning.
         let dc = ctx.dir_cache.clone();
-        let rt = tokio::runtime::Runtime::new()?;
+        let rt = crate::runtime::runtime();
         rt.block_on(async { dc.write().await.set(resolved).await });
 
         info!(count, "directory cache updated");

apps/infrastructure/src/tools/workflow.rs

@@ -65,7 +65,7 @@ impl Tool for WorkflowRun {
             zesdex_domain::agent::defaults::DEFAULT_MODEL.to_string(),
             None,
         );
-        let rt = tokio::runtime::Runtime::new()?;
+        let rt = crate::runtime::runtime();
         let result: Vec<String> =
             rt.block_on(async { execute_workflow(&script, ctx, &llm_client).await })?;
 
@@ -229,7 +229,7 @@ impl Tool for HiveMind {
             .ok_or_else(|| anyhow::anyhow!("missing 'cycles' array"))?;
 
         info!("Hive mind starting with {} cycles", cycles_val.len());
-        let rt = tokio::runtime::Runtime::new()?;
+        let rt = crate::runtime::runtime();
         let mut all_node_outputs = Vec::new();
 
         for (cycle_idx, cycle_val) in cycles_val.iter().enumerate() {