* fix: tidy agents home, mobile logo, and PWA dev/icon issues
- Remove recent-runs cards from the new agent page
- Scale the ASCII logo to fit narrow viewports instead of overflowing
- Serve manifest in dev and skip SW registration in dev to clear console errors
- Use a flat, opaque apple-touch-icon so iOS stops adding a black border
- Ignore generated ui/dev-dist
* feat: add send button and prevent iOS focus-zoom on chat input
- Add a circular send button (accent, spinner while sending) to the prompt bar
- Bump textarea to 16px on mobile so iOS doesn't zoom the viewport on focus
* fix: polish prompt bar and center logo
- Center the ASCII logo at all widths
- Prevent iOS focus-zoom via viewport maximum-scale instead of bumping the
input to 16px, so mobile text stays the intended size
- Give the model picker a chip/chevron treatment to anchor it next to the send button
* fix: simplify model picker to plain text + chevron
* fix: tighten prompt bar padding and shrink send button
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Co-authored-by: open-swe[bot] <215916821+open-swe[bot]@users.noreply.github.com>