Previously `historyItems` was seeded empty and the intro (with Banner +
SessionPanel) was only pushed after Python's `session.create` returned —
~1.8s of agent + tools + MCP init with nothing on screen. Base CLI feels
instant because it prints the banner as its first action.
Seed `historyItems` with an info-less intro on mount. `appLayout` now
renders the Banner unconditionally for `kind === 'intro'` and gates only
the SessionPanel on `info` being present. Gateway.ready swaps the skin
(~200ms) and session.info fills in the panel when the agent is ready.
Net: first usable frame drops from ~2s to ~300ms (node + module graph +
React mount). No behavior change — intro message is replaced in place
by `introMsg(info)` when `newSession()` / `resumeById()` resolve.
Hoist turn state from a 286-line hook into $turnState atom + turnController
singleton. createGatewayEventHandler becomes a typed dispatch over the
controller; its ctx shrinks from 30 fields to 5. Event-handler refs and 16
threaded actions are gone.
Fold three createSlash*Handler factories into a data-driven SlashCommand[]
registry under slash/commands/{core,session,ops}.ts. Aliases are data;
findSlashCommand does name+alias lookup. Shared guarded/guardedErr combinator
in slash/guarded.ts.
Split constants.ts + app/helpers.ts into config/ (timing/limits/env),
content/ (faces/placeholders/hotkeys/verbs/charms/fortunes), domain/ (roles/
details/messages/paths/slash/viewport/usage), protocol/ (interpolation/paste).
Type every RPC response in gatewayTypes.ts (26 new interfaces); drop all
`(r: any)` across slash + main app.
Shrink useMainApp from 1216 -> 646 lines by extracting useSessionLifecycle,
useSubmission, useConfigSync. Add <Fg> themed primitive and strip ~50
`as any` color casts.
Tests: 50 passing. Build + type-check clean.
