Cannot render unicode U+2B55 ⭕

[yhuang85]

Describe the bug
A clear and concise description of what the bug is.
The unicode U+2B55 is not rendered in .gif

To Reproduce
Steps to reproduce the behavior:

1. Run asciinema rec demo.cast
2. Copy & paste the unicode char ⭕ in the terminal and press enter
3. Ctrl-d to end recording
4. Run agg demo.cast demo.gif
5. You will not see the unicode in demo.gif

Expected behavior
A clear and concise description of what you expected to happen.

Versions:

• OS: WSL2 Ubuntu
• agg: 1.4.3

Additional context
Add any other context about the problem here.

[Freed-Wu]

Seems all non-ascii unicode character cannot be displayed.

For example. https://asciinema.org/a/660633

agg https://asciinema.org/a/660633 demo.gif
xdg-open demo.gif

[Freed-Wu]

And the render in website still have many incorrect result: https://asciinema.org/a/660635

[ku1ik]

While not ideal, the recently released agg 1.5.0 has improved rendering around unicode/emoji/double-width chars: https://github.com/asciinema/agg/releases/tag/v1.5.0

Below's the result of agg --font-size 28 https://asciinema.org/a/660633 issue-70.gif

There's still problem with characters moving/jumping a bit when the cursor movement is involved, which is likely related to this shortcoming in avt: asciinema/avt#19