feat: add interactive wizards for `sr create` and `sr add-update` (#23)
When required flags are missing and stdin is a TTY, launch a step-by-step
wizard using charmbracelet/huh instead of erroring out. Flags still work
for scripting and CI — non-TTY/--json mode returns a clear missing-flags
error.
Wizard features:
- Status page select with URL display (sr create)
- Component multi-select from the selected page (sr create)
- Status report select with unresolved-first filtering (sr add-update)
- Multi-line message input for create, single-line for add-update
- Summary note + confirmation before submission
- Ctrl+C prints "Aborted." and exits 130
Also adds IsStdinTerminal() to internal/cli for proper stdin TTY detection.