feat(sdk): initial package bootstrap for SDK (#18861)

packages/sdk/README.md

@@ -0,0 +1,36 @@
+# @google/gemini-cli-sdk
+
+The Gemini CLI SDK provides a programmatic interface to interact with Gemini
+models and tools.
+
+## Installation
+
+```bash
+npm install @google/gemini-cli-sdk
+```
+
+## Usage
+
+```typescript
+import { GeminiCliAgent } from '@google/gemini-cli-sdk';
+
+async function main() {
+  const agent = new GeminiCliAgent({
+    instructions: 'You are a helpful assistant.',
+  });
+
+  const controller = new AbortController();
+  const signal = controller.signal;
+
+  // Stream responses from the agent
+  const stream = agent.sendStream('Why is the sky blue?', signal);
+
+  for await (const chunk of stream) {
+    if (chunk.type === 'content') {
+      process.stdout.write(chunk.value.text || '');
+    }
+  }
+}
+
+main().catch(console.error);
+```