fix(site): restore team avatar framing

[ilyar]

Summary

• keep team photo frames square after explicit avatar dimensions were added
• update visual baselines for the repaired team/contact viewports
• add an acceptance assertion that avatar frames and images stay square

Why this happened

The previous visual baselines had been regenerated after adding avatar width/height attributes, but the CSS did not constrain the image height inside the card. The screenshot tests then approved that broken state, so later acceptance runs compared against the broken screenshots. This PR adds a geometry assertion so a broken photo frame cannot be accepted just by refreshing PNG baselines.

Validation

• npm run lint
• npm run acceptance:test
• npm run lighthouse

[Glazlk]

Reviewed: correct fix for the team avatar framing regression. Moving aspect-ratio to .team__photo (container) with overflow:hidden and width/height:100% + object-fit:cover on the image is more robust than aspect-ratio on the img. The geometry assertion (square frame + image fills frame) is a solid regression guard against PNG-only approvals. CI green (lint, build, acceptance incl. new assertion, lighthouse). LGTM.