feat: tab completions for file paths (#279)

Made a PR as was requested in the #113

codex-cli/src/components/chat/multiline-editor.tsx

@@ -155,6 +155,8 @@ export interface MultilineTextEditorHandle {
   isCursorAtLastRow(): boolean;
   /** Full text contents */
   getText(): string;
+  /** Move the cursor to the end of the text */
+  moveCursorToEnd(): void;
 }
 
 const MultilineTextEditorInner = (
@@ -372,6 +374,16 @@ const MultilineTextEditorInner = (
         return row === lineCount - 1;
       },
       getText: () => buffer.current.getText(),
+      moveCursorToEnd: () => {
+        buffer.current.move("home");
+        const lines = buffer.current.getText().split("\n");
+        for (let i = 0; i < lines.length - 1; i++) {
+          buffer.current.move("down");
+        }
+        buffer.current.move("end");
+        // Force a re-render
+        setVersion((v) => v + 1);
+      },
     }),
     [],
   );