refactor(agent): streamline hook method calls and enhance error logging

- Introduced a helper method `_for_each_hook_safe` to reduce code duplication in hook method implementations.
- Updated error logging to include the method name for better traceability.
- Improved the `SkillsLoader` class by adding a new method `_skill_entries_from_dir` to simplify skill listing logic.
- Enhanced skill loading and filtering logic, ensuring workspace skills take precedence over built-in ones.
- Added comprehensive tests for `SkillsLoader` to validate functionality and edge cases.

nanobot/agent/hook.py

@@ -67,40 +67,27 @@ class CompositeHook(AgentHook):
     def wants_streaming(self) -> bool:
         return any(h.wants_streaming() for h in self._hooks)
 
-    async def before_iteration(self, context: AgentHookContext) -> None:
+    async def _for_each_hook_safe(self, method_name: str, *args: Any, **kwargs: Any) -> None:
         for h in self._hooks:
             try:
-                await h.before_iteration(context)
+                await getattr(h, method_name)(*args, **kwargs)
             except Exception:
-                logger.exception("AgentHook.before_iteration error in {}", type(h).__name__)
+                logger.exception("AgentHook.{} error in {}", method_name, type(h).__name__)
+
+    async def before_iteration(self, context: AgentHookContext) -> None:
+        await self._for_each_hook_safe("before_iteration", context)
 
     async def on_stream(self, context: AgentHookContext, delta: str) -> None:
-        for h in self._hooks:
-            try:
-                await h.on_stream(context, delta)
-            except Exception:
-                logger.exception("AgentHook.on_stream error in {}", type(h).__name__)
+        await self._for_each_hook_safe("on_stream", context, delta)
 
     async def on_stream_end(self, context: AgentHookContext, *, resuming: bool) -> None:
-        for h in self._hooks:
-            try:
-                await h.on_stream_end(context, resuming=resuming)
-            except Exception:
-                logger.exception("AgentHook.on_stream_end error in {}", type(h).__name__)
+        await self._for_each_hook_safe("on_stream_end", context, resuming=resuming)
 
     async def before_execute_tools(self, context: AgentHookContext) -> None:
-        for h in self._hooks:
-            try:
-                await h.before_execute_tools(context)
-            except Exception:
-                logger.exception("AgentHook.before_execute_tools error in {}", type(h).__name__)
+        await self._for_each_hook_safe("before_execute_tools", context)
 
     async def after_iteration(self, context: AgentHookContext) -> None:
-        for h in self._hooks:
-            try:
-                await h.after_iteration(context)
-            except Exception:
-                logger.exception("AgentHook.after_iteration error in {}", type(h).__name__)
+        await self._for_each_hook_safe("after_iteration", context)
 
     def finalize_content(self, context: AgentHookContext, content: str | None) -> str | None:
         for h in self._hooks: