AppConfig help_url default falls back to localhost instead of production URL

[dennisthemenacing]

Opened on behalf of @BeckettFrey

Summary

AppConfig in src/voxkit/config/app_config.py uses http://localhost:3000/help as the hardcoded default for help_url in two places:

1. Dataclass field default (line 131):

   help_url: str = "http://localhost:3000/help"

2. YAML fallback in from_yaml (line 160):

   help_url=data.get("help_url", "http://localhost:3000/help"),

Meanwhile, all actual YAML config files (config/app_info.yaml, config/profiles/default/app_info.yaml, config/profiles/explanatory/app_info.yaml) correctly use the production URL https://voxkit-web.vercel.app/help, and startup_config.py also has the correct URL.

Problem

If a YAML config file is missing the help_url key, or if AppConfig is constructed without explicitly setting help_url, the fallback is a localhost URL that won't work for end users. The help button (gui/__init__.py:331) opens self.app_config.help_url via webbrowser.open, so this would silently fail.

The legacy src/voxkit/config.py also still contains HELP_URL = "http://localhost:3000/help", though it appears to be superseded by startup_config.py.

Suggested fix

• Update the two defaults in app_config.py to https://voxkit-web.vercel.app/help
• Update the corresponding test assertions in tests/config/test_app_config.py (lines 55, 110)
• Consider removing or deprecating the stale src/voxkit/config.py HELP_URL since startup_config.py is the canonical source