feat(initial): scaffold @push.rocks/smartchat with core, CLI, and web layers

Three-layer architecture built on @push.rocks/smartagent:
- ts/ — ChatSession wrapping runAgent() with conversation state management
- ts_cli/ — ink-based terminal chat TUI (React.createElement, no JSX)
- ts_web/ — Lit web components (smartchat-window, smartchat-message, smartchat-input)

ts_cli/plugins.ts

@@ -0,0 +1,21 @@
+// ink (React-based terminal UI)
+import { render, Box, Text, Static, Newline, Spacer, useInput, useApp } from 'ink';
+export { render, Box, Text, Static, Newline, Spacer, useInput, useApp };
+
+// ink components
+import TextInput from 'ink-text-input';
+export { TextInput };
+
+// React
+import React from 'react';
+export { React };
+export const h = React.createElement;
+
+// Core (cross-folder import)
+import { ChatSession } from '../ts/smartchat.classes.chatsession.js';
+export { ChatSession };
+export type { IChatSessionOptions, IChatCallbacks, IChatUsage } from '../ts/smartchat.interfaces.js';
+
+// smartagent types
+export type { IAgentRunResult } from '@push.rocks/smartagent';
+export type { LanguageModelV3, ToolSet } from '@push.rocks/smartai';