docs: README.md has stale status, Tauri references, em dashes, Title Case, first-person singular

[forkwright]

• Status section (L112): says "Scaffolded. Research phase complete... Not yet under active development" but Wave 1 (kryphos, 7 PRs) and Wave 2 (syntonia, 7 PRs) are both complete
• Tauri listed as desktop framework in 2 places (L33, L98) but superseded by Dioxus (roadmap R26)
• 4 em dashes (L106-108 in doc links, L128 inline) — banned per WRITING.md
• Title Case: What It Does → What it does, Design Constraints → Design constraints
• 3 first-person singular instances (L7, L112, L114): "I keep coming back...", "I don't know if...", "I keep thinking about..." — banned in technical docs per WRITING.md
• L87: MSRV 1.85 hardcoded — will drift, authoritative value is in Cargo.toml