feat(tui): add plugin context hook

packages/plugin/src/tui/index.ts

@@ -1 +1,2 @@
 export * as Plugin from "./plugin.js"
+export { PluginContextProvider, usePlugin } from "./solid.js"

packages/plugin/src/tui/solid.ts

@@ -0,0 +1,19 @@
+import { createComponent, createContext, useContext, type JSX } from "solid-js"
+import type { Context } from "./context.js"
+
+const PluginContext = createContext<Context>()
+
+export function PluginContextProvider(props: { readonly value: Context; readonly children: JSX.Element }) {
+  return createComponent(PluginContext.Provider, {
+    value: props.value,
+    get children() {
+      return props.children
+    },
+  })
+}
+
+export function usePlugin() {
+  const context = useContext(PluginContext)
+  if (!context) throw new Error("PluginContextProvider is missing")
+  return context
+}