Full Russian site · localized Skill collections · BYOK hardening

The Russian site is now fully translated. Previously only part of the site had Russian copy, so the homepage, product pages, tool pages and documentation fell back to English mid-visit.
The Russian product homepage now renders in Russian end to end, including the hero composer's mode chips, feature sections, FAQ and audience cards.
Russian tool pages, the friend links page and site navigation are localized, so you can browse the whole site in Russian without switching back to English.

You can now maintain localized names and descriptions for Skill collections, so members see collection copy in their own language.
Fixed shared Skill cards that lost their localized text and rendered in the source language instead.
Skill metadata imported from a team now keeps its localized display fields instead of showing raw imported values.
Featured collection copy on the Skills page is localized rather than falling back to English.

Hardened how customer-provided model credentials (BYOK) are bound to a workspace, so a credential can no longer be referenced across workspace boundaries.
Tightened ownership checks on custom provider endpoints.

Fixed inconsistent header spacing across pages, and restored the resource page's padding.
Improved readability of Skill card descriptions.