Initial commit of Gemini Code CLI

This commit introduces the initial codebase for the Gemini Code CLI, a command-line interface designed to facilitate interaction with the Gemini API for software engineering tasks.

The code was migrated from a previous git repository as a single squashed commit.

Core Features & Components:

*   **Gemini Integration:** Leverages the `@google/genai` SDK to interact with the Gemini models, supporting chat history, streaming responses, and function calling (tools).
*   **Terminal UI:** Built with Ink (React for CLIs) providing an interactive chat interface within the terminal, including input prompts, message display, loading indicators, and tool interaction elements.
*   **Tooling Framework:** Implements a robust tool system allowing Gemini to interact with the local environment. Includes tools for:
    *   File system listing (`ls`)
    *   File reading (`read-file`)
    *   Content searching (`grep`)
    *   File globbing (`glob`)
    *   File editing (`edit`)
    *   File writing (`write-file`)
    *   Executing bash commands (`terminal`)
*   **State Management:** Handles the streaming state of Gemini responses and manages the conversation history.
*   **Configuration:** Parses command-line arguments (`yargs`) and loads environment variables (`dotenv`) for setup.
*   **Project Structure:** Organized into `core`, `ui`, `tools`, `config`, and `utils` directories using TypeScript. Includes basic build (`tsc`) and start scripts.

This initial version establishes the foundation for a powerful CLI tool enabling developers to use Gemini for coding assistance directly in their terminal environment.

---
Created by yours truly: __Gemini Code__

packages/cli/src/ui/components/Header.tsx

@@ -0,0 +1,38 @@
+import React from 'react';
+import { Box, Text } from 'ink';
+import { UI_WIDTH, BOX_PADDING_X } from '../constants.js';
+import { shortenPath } from '../../utils/paths.js';
+
+interface HeaderProps {
+    cwd: string;
+}
+
+const Header: React.FC<HeaderProps> = ({ cwd }) => {
+    return (
+        <>
+            {/* Static Header Art */}
+            <Box marginBottom={1}>
+                <Text color="blue">{`
+   ______  ________  ____    ____  _____  ____  _____  _____
+ .' ___  ||_   __  ||_   \\  /   _||_   _||_   \\|_   _||_   _|
+/ .'   \\_|  | |_ \\_|  |   \\/   |    | |    |   \\ | |    | |
+| |   ____  |  _| _   | |\\  /| |    | |    | |\\ \\| |    | |
+\\ \`.___]  |_| |__/ | _| |_\\/_| |_  _| |_  _| |_\\   |_  _| |_
+ \`._____.'|________||_____||_____||_____||_____|\\____||_____|`}</Text>
+            </Box>
+            {/* CWD Display */}
+            <Box
+                borderStyle="round"
+                borderColor="blue"
+                paddingX={BOX_PADDING_X}
+                flexDirection="column"
+                marginBottom={1}
+                width={UI_WIDTH}
+            >
+                <Box paddingLeft={2}><Text color="gray">cwd: {shortenPath(cwd, /*maxLength*/ 70)}</Text></Box>
+            </Box>
+        </>
+    );
+};
+
+export default Header;