* feat(app): group project settings into Worktree / Scripts / Metadata
Adds SettingsGroup component (title + info tooltip + trailing slot) and
restructures the project settings screen into three categorized groups
with explanatory tooltips. Metadata prompt labels drop the "prompt"
suffix now that they live under a "Metadata generation" group, and
placeholders read as example instructions a real user would write.
Applies useWebScrollbarStyle to the settings ScrollViews.
* Add ExternalLink component and docs links to project settings
