[BUG] Drag-and-drop / Cmd+V image attach works at `claude agents` list view but is silently dropped inside an agent session

Summary

In claude agents v2.1.143 on macOS, attaching an image works at the top-level session list but silently fails once I enter an individual agent session. No [Pasted image #N] placeholder appears, no error is shown — the drop / paste is just ignored.

This affects both drag-and-drop from Finder and Cmd+V from clipboard, which makes me think the session view is mounting an input handler that's missing the image attach pipeline that the list view has.

Environment

• Claude Code version: 2.1.143
• OS: macOS (Darwin 25.2.0)
• Terminal: Ghostty (TERM=xterm-ghostty)
• Shell: zsh
• No image-related hooks in ~/.claude/settings.json

Reproduction

1. Run claude agents.
2. At the session list view, drag a PNG from Finder onto the window (or Cmd+V an image from clipboard).

• ✅ Image attaches; [Pasted image #1] placeholder appears.

1. Enter any agent session (existing or new).
2. Drag the same PNG onto the window, or Cmd+V the same clipboard image.

• ❌ Nothing happens. No placeholder, no error, no visual feedback.

Expected

Image attach should behave the same inside a session as it does at the list view — show [Pasted image #N] and include the image in the next message.

Workaround

Capture the screenshot to disk (e.g. pngpaste ~/Desktop/clip.png) and reference the file path as text in the prompt. The agent reads the file fine; it's only the in-input attach that's broken.

Notes

• Worked correctly a few days ago — this is a recent regression.
• v2.1.143 changelog mentions paste-related fixes for Windows Terminal / WSL; this looks like a macOS-side equivalent that slipped through, scoped specifically to the session view.