feat(about): brand-forward About redesign

[rgvxsthi]

Reworks the About screen into a brand-forward page that fits centered on every iPhone without scrolling.

What changed

• Brand hero — the logo art now fills a glass squircle edge-to-edge (clipped + glass rim), with a slow breathing accent aura behind it (respects Reduce Motion). Wordmark, tagline, and a tappable version chip sit below.
• Version chip keeps the existing 7-tap developer unlock (toasts, haptics, bounce) intact.
• Description — one refined product paragraph (dropped the old "LLM-native" pill/row).
• Project section — a single grouped card: Source on GitHub, Join the community (Discord), License (CC BY 4.0). Icon tiles use the same neutral white-glass style as the Settings rows.
• Fit — content is centered and scaled to the viewport via a self-contained fitted band; accessibility Dynamic Type sizes fall back to a ScrollView.
• Removed the old Credits section and the copyright footer.

Testing

• Simulator build + on-device (unsigned IPA) across iPhone sizes.
• Verified Reduce Motion disables the aura animation.