feat(skill_mcp): add dynamic truncation and grep filtering

- Add skill_mcp and webfetch to TRUNCATABLE_TOOLS list
- Add grep parameter for regex filtering of output lines
- Prevents token overflow from large MCP responses

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

src/hooks/tool-output-truncator.ts

@@ -16,6 +16,9 @@ const TRUNCATABLE_TOOLS = [
   "ast_grep_search",
   "interactive_bash",
   "Interactive_bash",
+  "skill_mcp",
+  "webfetch",
+  "WebFetch",
 ]
 
 interface ToolOutputTruncatorOptions {