In-canvas modals were locked to screen-centre. Add a green move-arrow
grip beside the ✕ that drags the dialog; positioning is an offset from
centre applied via asymmetric padding. The drag offset is clamped to the
window so a dialog stops at the edge instead of being squeezed, and the
offset resets when the dialog closes so each opens centred.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Start Plan B — replace the daemon's pop-up OS windows with in-canvas
modal overlays so dialogs work identically on native (one main window)
and web (canvas only).
- New `ui::modal::modal(base, content, on_close)`: dims the view behind
a backdrop that blocks clicks but does NOT dismiss, frames the content,
and adds a top-right ✕ as the sole close affordance. Sizes to the
content (no `Fill`), so dialogs shrink to fit.
- view_main stacks the active modal on top, so both run paths show it.
- Migrate About as the pilot: `about_open` bool + AboutOpen/AboutClose
instead of an OS window; About's view shrinks to content.
Remaining dialogs migrate to the same pattern next. Native + 75 tests OK.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
