Add embed responsive div only to Tainacan related embeds!

[mateuswetah]

Our current use of embed_oembed_html filter:

tainacan/src/classes/class-tainacan-embed.php

Line 27 in 4e14364

add_filter('embed_oembed_html', [$this, 'responsive_embed'], 10, 3);

Wraps every embeded element with a .tainacan-embed-container div, which might cause conflicts especially if a theme is using the new responsive-embeds support option. We should find a way to have this used only in situations related to plugin. A suggestion made so far was to have a filter by the_content...

also, check this discussion in portuguese:
https://tainacan.discourse.group/t/conflito-de-estilos-em-elementos-embed/79/15

[mateuswetah]

In any case, we should also improve our own embed responsiveness class... There are a lot of things being assumed on CSS that are not safe for the diversity of content that can be rendered.

I was investigating if maybe we could use Gutenberg blocks in somehow to display our content, as they work very well. Maybe if we can not make this "programmatically", we could just learn from their code. They check the iframes height and width attributes to decide among classes that handle the ratio properly (so not only for YouTube):

https://github.com/WordPress/gutenberg/blob/baffdc7f880e5e9b68d7cb38fd17758f3e0c2bbd/packages/block-library/src/embed/constants.js#L1

https://github.com/WordPress/gutenberg/blob/baffdc7f880e5e9b68d7cb38fd17758f3e0c2bbd/packages/block-library/src/embed/util.js#L183