Very frequent log messages about font fallback

[kaimast]

When running the examples I get very frequent (dozens per second) log messages like that:

[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'Noto Sans'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'DejaVu Sans'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'FreeSans'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'Noto Sans Mono'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'DejaVu Sans Mono'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'FreeMono'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'Noto Sans Symbols'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] failed to find family 'Noto Sans Symbols2'
[2023-06-04T20:40:18Z DEBUG cosmic_text::font::fallback] Failed to find preset fallback for [] locale 'en-US', used 'Verdana': 'Word'

It seems like the library is constantly trying to resolve fallback fonts instead of doing it once and caching the outcome.

The resulting performance is extremely bad as well. For example, I need to run the editor in release mode for it to be somewhat responsive.

[kaimast]

I don't think this is fixed for me... Cosmic still creates a bunch of log messages ever time I type a letter.