Fix final Financial Stream minor accessibility issues

[Financialstream]

Scope

Final minor maintenance pass only.

Confirmed accessibility defect

Repository-wide source QA found 25 RU production pages where the mobile menu button had no accessible name because its only inner text was aria-hidden and the button had no aria-label.

Added exactly aria-label="Открыть меню" only to those buttons. Existing RU buttons that already had a non-empty accessible name were left unchanged.

The affected set includes the originally identified pages plus ru/start-here/index.html, six RU service-detail pages, and legacy RU article pages with the same source-level defect.

aria-expanded, aria-controls, the controlled panel IDs, markup structure, and existing menu JS were preserved.

Flagship Twitter metadata

Added exactly one twitter:image:alt immediately after the existing twitter:image on:

• blog/us-bookkeeping-small-business.html
• ru/blog/buhgalteriya-ssha-malogo-biznesa.html

Existing Twitter image, OG image, canonical, hreflang, Article schema, FAQ schema, and Breadcrumb schema were preserved.

Source QA

A temporary branch-only GitHub Actions QA/patch workflow was used solely to perform deterministic exact replacements and repository-wide assertions because the connector has no partial-file patch primitive for large HTML files.

The successful QA run verified:

• every RU data-menu-toggle has a non-empty accessible name;
• aria-expanded="false" remains present;
• every aria-controls target exists in the same document;
• the exact expected 25 unlabeled RU buttons were the only accessibility targets patched;
• both flagship pages contain exactly one twitter:image:alt;
• Twitter images and OG images remain unchanged;
• canonical and required hreflang remain unchanged;
• Article, FAQPage, and BreadcrumbList schema blocks remain present exactly once;
• git diff --check passes;
• changed production files are HTML only.

The temporary workflow has been deleted and is not part of the final PR diff.

Final diff boundaries

No CSS, JS, images, About pages, visual design, article body copy, service body copy, business facts, counters, sitemap, portrait, flagship hero, canonical, hreflang, or schema content were changed.

Browser runtime QA: NOT VERIFIED.