[Bug]: f-string expression part cannot include a backslash in preview.py

[carry-xz]

Affected Software/Harness

cli-hub

Version / Commit

latest (main branch commit: dc73924)

Operating System

macOS

Python Version

3.10+

Steps to Reproduce

1. Install cli-hub: pip install cli-anything-hub
2. Run: cli-hub list
3. See SyntaxError occur

Expected Behavior

The cli-hub list command should execute successfully and display the list of available CLIs.

Actual Behavior

A SyntaxError is raised during module import:

SyntaxError: f-string expression part cannot include a backslash

The error prevents the entire cli-hub CLI from loading.

Relevant Logs / Tracebacks

Traceback (most recent call last):
  File "/opt/homebrew/bin/cli-hub", line 3, in <module>
    from cli_hub.cli import main
  File "/opt/homebrew/lib/python3.10/site-packages/cli_hub/cli.py", line 46, in <module>
    from cli_hub.preview import (
  File "/opt/homebrew/lib/python3.10/site-packages/cli_hub/preview.py", line 725
    )
    ^
SyntaxError: f-string expression part cannot include a backslash

Additional Context

Root Cause:
In cli-hub/cli_hub/preview.py line 723, the _render_trajectory_html_section() function contains an f-string with escaped quotes in the expression:

f'<div class="trajectory-list">{items_html or "<div class=\"artifact-file\">No step timeline entries yet.</div>"}</div>'

Python 3.10+ prohibits backslashes inside f-string expression curly braces {}.

Fix:
Extract the nested HTML string to a variable before using it in the f-string:

empty_message = '<div class="artifact-file">No step timeline entries yet.</div>'
items_html = "..."  # existing computation

return (
    '<section class="section">'
    "<h2>Trajectory</h2>"
    f'<div class="facts">{cards_html}</div>'
    f'<div class="trajectory-list">{items_html or empty_message}</div>'
    "</section>"
)

This maintains full functionality while avoiding backslashes in f-string expressions.