Stream lstk logs lines to real terminal scrollback

[anisaoshafi]

• Interactive lstk logs capped history at 200 lines and repainted it in place, so terminal scrollback stopped growing past that point (unlike docker logs / --non-interactive).
• LogLineEvent now prints permanently above the TUI via a new output.NewStreamingLogSink + Program.Println, bypassing the capped buffer.
• Printed synchronously (not via tea.Cmd) to keep lines in order — Bubble Tea runs returned Cmds concurrently, which reordered lines in an earlier pass.

Test plan

• Unit tests for the new sink
• New integration test: 550 lines on a real container, lstk logs under a real PTY, all survive in order
• make test + make lint clean
• Manually verified against a real emulator (600 lines, real PTY)
• --non-interactive unchanged

Closes DEVX-1027

[skyrpex]

Thanks, now the lstk logs command is really useful 👍🏻