Direct nav to /goals/new used to render the index page with an empty
modal frame because the entire template was wrapped in DS::Dialog.
The URL was effectively un-shareable.
Branch on turbo_frame_request? — Turbo Frame requests still render
the DS::Dialog wrapper (the existing in-modal flow on the index page
keeps working). Non-frame requests render a standalone page-level
header (h1 + subtitle + icon) followed by the form_stepper partial.
Same Stimulus controller, same data-goal-stepper-modal-subtitle
selector, so the stepper's subtitle update path works identically.
Controller sets @breadcrumbs so the standalone variant gets the
Home > Goals > New goal trail.
Verified both paths via Playwright: direct GET renders standalone
form with h1 "New goal" + no dialog; click-from-index opens the
DS::Dialog with the stepper inside.
628e1f89bb