Allow terminal image graphics protocol passthrough (Kitty graphics / Sixel) in terminal panes

[vasujan]

Environment

• Herdr Version: 0.8.0
• OS: macOS
• Tool: Yazi (and other terminal file managers like Ranger / LF / Superfile)

Description

When navigating media files (images, PDFs, videos) using CLI file managers like Yazi inside a Herdr pane,
media previewers fail and render binary replacement characters (▒▒▒▒▒▒▒▒▒▒▒▒▒▒) across the preview pane.

Outside Herdr (directly in Kitty / WezTerm / iTerm2), image and media previews function normally because the
terminal directly handles the graphics escape sequences.

Expected Behavior

Herdr should either:

1. Pass through terminal graphics escape protocols (Kitty graphics protocol \x1b_G... or Sixel \x1bP...)
   to the underlying host terminal emulator (similar to tmux's set -g allow-passthrough on).
2. Expose a configuration flag in Herdr to enable graphics escape sequence passthrough.

Steps to Reproduce

1. Open a Herdr workspace session.
2. Launch yazi in a pane and select an image or PDF file.
3. Observe binary control byte corruption (▒▒) in the preview pane instead of an image