fix: remove unused truncate function and extra blank lines

src/tui.test.ts

@@ -121,8 +121,6 @@ describe('readConfigInvalid', () => {
   });
 });
 
-
-
 describe('tui plugin env disable', () => {
   let originalEnv: typeof process.env;
 

src/tui.ts

@@ -91,10 +91,6 @@ export function getSidebarAgentNames(snapshot: TuiSnapshot): string[] {
     : FALLBACK_SIDEBAR_AGENTS;
 }
 
-function truncate(str: string, maxLen: number): string {
-  return str.length > maxLen ? `${str.slice(0, maxLen - 1)}…` : str;
-}
-
 function agentRow(
   label: string,
   model: string,