Contour Terminal Emulator

A lot has happened since our last release, and that was already too long ago. So now, it is finally time to tag a release, with an already way too long list of great improvements as well as fixes.

**Contour 0.7.0** makes the window a workspace: native GUI tabs in the title bar, split panes, saved layouts, and an optional terminal-styled UI that draws the application's own chrome on the character grid. It adds an experimental daemon mode for sessions that outlive the window showing them, accessibility support across the terminal and its chrome, the kitty graphics, text-sizing and clipboard protocols, ReGIS vector graphics, and a large round of VT conformance work.

### Tabs, splits and layouts

- Adds first-class GUI tabs presented in a custom window title bar, replacing the status-line tab list (the {Tabs} status-line directive remains supported for existing configs)
- Adds split panes — split the active pane vertically (Ctrl+Shift+E) or horizontally (Ctrl+Shift+O), close a pane (Ctrl+Shift+X), and move pane focus with Alt+Shift+Arrow
- Adds pane management actions: swap the active pane with a neighbor (Ctrl+Alt+Arrow), resize it (Ctrl+Shift+Alt+Arrow), flip a split's o