fix(electrobun): wizard 7 fixes — validation, GitLab, SSHFS, icons, model dropdown, keyboard nav
- Git Platform: validates repo via git.probe before enabling Next, supports GitHub + GitLab + any git URL
- Template dir configurable in Advanced Settings (template_dir key)
- SSHFS: checks sshfs availability, mountpoint selector when enabled
- CustomDropdown: flip-up when insufficient space below
- 50 Lucide icons (was 24) with categories (AI, Data, DevOps, Security, Media, Comms)
- Model: CustomDropdown from live API, max_tokens as slider, effort only with adaptive thinking
- Keyboard: Escape closes wizard, Tab navigation with :focus-visible rings, source cards navigable