feat(frontend,wire): surface system (FE slice 1) + @dispatch/wire types-only split (B2)

FE slice 1 — backend-declared, frontend-agnostic surface system (verified live): new types-only @dispatch/ui-contract (SurfaceSpec / field kinds / region / ActionRef / catalog), surface-registry (typed service handle), transport-ws (Bun WS :24205, path-agnostic upgrade), surface-loaded-extensions (first real surface); kernel HostAPI.getExtensions; host-bin wiring; bin/up. Harness: retire AGENTS 'backend only', ORCHESTRATOR §3/§7/§8, frontend-design.md locked.

B2 — wire-types split (chat-slice prerequisite): new types-only @dispatch/wire single-sources the wire ABI (AgentEvent + 11 variants; conversation model Chunk/ChatMessage/Role/TurnId/StepId + 6 chunk variants; Usage) with zero @dispatch/* deps. @dispatch/kernel re-exports via shims so its public surface is byte-identical (zero consumer blast radius). transport-contract re-exports AgentEvent from @dispatch/wire and drops its @dispatch/kernel dependency, so HTTP clients (the web frontend) consume the wire without the kernel runtime.

tsc -b + biome clean; 460 vitest + 77 bun pass.

1 files changed, 3 insertions, 1 deletions

diff --git a/AGENTS.md b/AGENTS.md
index 174abc7..f173a7e 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -7,7 +7,9 @@
 ## What this project is
 A **minimal kernel + extensions** agent runtime. The kernel runs ONE agent turn
 and hosts extensions. Every feature is an extension. Tiers: **kernel → core →
-standard**. Backend only for now (no frontend).
+standard**. The web frontend is a SEPARATE repo (`../dispatch-web`), built to
+the same methodology and consuming the backend's typed contracts (see
+`notes/frontend-design.md`).
 
 ## Stack
 Bun + TypeScript (strict, project references via `tsc -b`). Biome for