perf(agent): eksekusi tool read-only paralel seperti Claude Code

Sebelumnya loop utama mengeksekusi semua tool call satu-per-satu
(sequential for loop). Seperti Claude Code, tool read-only yang
independen dalam satu pesan assistant (read/grep/glob/semantic_search
dsb.) kini dijalankan konkuren dengan bounded parallelism (max 8),
mengurangi latensi per turn secara signifikan untuk beban coding.

- feat(registry): tool_is_parallel_safe() — whitelist tool read-only
  yang aman dijalankan paralel; tool mutating/shell tetap sequential
- feat(executor): is_parallel_safe() delegasi ke registry; ToolExecutor
  trait Default=false (konservatif)
- fix(application): execute_tool_calls_in_parallel() — join_all +
  semaphore bounded 8, hasil dikumpulkan dalam URUTAN panggilan asli
  (kontrak OpenAI/Anthropic tool-result ordering)
- loop utama: batch paralel hanya jika SEMUA tool parallel-safe; jika
  ada satu tool mutating, jatuh balik ke jalur sequential aman
- test: +2 registry test, +2 application test (konkurensi & urutan,
  fallback batch mutating)

apps/infrastructure/src/tools/executor.rs

@@ -15,6 +15,13 @@ impl InfrastructureToolExecutor {
             tools: all_tools(),
         }
     }
+
+    /// Whether a tool is read-only and safe to execute concurrently with
+    /// other parallel-safe tools. Delegates to the registry so the main
+    /// turn loop and subagent engine share one source of truth.
+    pub fn is_parallel_safe(tool_name: &str) -> bool {
+        crate::tools::tool_is_parallel_safe(tool_name)
+    }
 }
 
 impl ToolExecutor for InfrastructureToolExecutor {
@@ -37,4 +44,8 @@ impl ToolExecutor for InfrastructureToolExecutor {
             }
         }
     }
+
+    fn is_parallel_safe(&self, tool_name: &str) -> bool {
+        Self::is_parallel_safe(tool_name)
+    }
 }