[ARCH-02/GEN-11] README + CLAUDE.md drift: lists removed `willow-channel` crate, wrong EventKind count

[intendednull]

Commit: 2f26d91 · Finding: ARCH-02 / GEN-11 (merged)

Problem

• README.md:29-65 still lists willow-channel as a live crate and shows a "Channels" module in the architecture ASCII diagram. The crate was removed per docs/specs/2026-04-12-willow-channel-removal.md. grep willow-channel crates/ → 0 hits.
• README.md:48-55 claims ~22 EventKind variants; CLAUDE.md claims 17; actual count in crates/state/src/event.rs is ~24.
• README does not list willow-agent in the crates table, though it is documented in CLAUDE.md.

Fix

• Drop the willow-channel row from the README crates table and the "Channels" box from the architecture diagram.
• Add willow-agent to the README crates table.
• Stop citing an exact variant count in prose — either auto-generate it from event.rs, or drop the number and describe the shape in English.

Obvious fix — will be auto-PR'd.