feat(aircoding): AirCoding V2 baseline — deterministic multi-agent architecture

Forked from OpenCode v1.17.4 with multi-agent system:
- 5 agents: aircoding, scheduler, worker, architect, reviewer
- Deterministic DAG scheduling engine (coordinator_tick)
- Tool whitelists as hard enforcement
- AirCoding validation plugin
- V1 requirements: C4 docs, ADR, AGENTS.md, debug-log.md
- Design documents in docs/

packages/tui/src/component/spinner.tsx

@@ -0,0 +1,24 @@
+import { Show } from "solid-js"
+import { useTheme } from "../context/theme"
+import { useKV } from "../context/kv"
+import type { JSX } from "@opentui/solid"
+import type { RGBA } from "@opentui/core"
+import "opentui-spinner/solid"
+
+export const SPINNER_FRAMES = ["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"]
+
+export function Spinner(props: { children?: JSX.Element; color?: RGBA }) {
+  const { theme } = useTheme()
+  const kv = useKV()
+  const color = () => props.color ?? theme.textMuted
+  return (
+    <Show when={kv.get("animations_enabled", true)} fallback={<text fg={color()}>⋯ {props.children}</text>}>
+      <box flexDirection="row" gap={1}>
+        <spinner frames={SPINNER_FRAMES} interval={80} color={color()} />
+        <Show when={props.children}>
+          <text fg={color()}>{props.children}</text>
+        </Show>
+      </box>
+    </Show>
+  )
+}