[P0][CLI] Text not cleared when entering second API key

## Description
When entering two API keys (e.g., one Anthropic agent and one OpenAI agent), after entering the first key, the text is not cleared to enter the second key.

## Category
UI/UX Bug

## Flow
Flow 4: LangChain Agent Add/Remove Cycle

## Test Path
CLI

## Priority
P0

## Reporter
eshkuma