chore: release v0.1.9 (#353)

This PR updates the version to 0.1.9 after publishing to PyPI.

## Changes
- Updated version in `pyproject.toml` to 0.1.9
- Updated version in `src/claude_agent_sdk/_version.py` to 0.1.9
- Updated `CHANGELOG.md` with release notes

## Release Information
- Published to PyPI: https://pypi.org/project/claude-agent-sdk/0.1.9/
- Bundled CLI version: 2.0.49
- Install with: `pip install claude-agent-sdk==0.1.9`

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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>

Author: github-actions[bot]

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 0.1.9
+
+### Internal/Other Changes
+
+- Updated bundled Claude CLI to version 2.0.49
+
 ## 0.1.8
 
 ### Features

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "claude-agent-sdk"
-version = "0.1.8"
+version = "0.1.9"
 description = "Python SDK for Claude Code"
 readme = "README.md"
 requires-python = ">=3.10"

src/claude_agent_sdk/_version.py

@@ -1,3 +1,3 @@
 """Version information for claude-agent-sdk."""
 
-__version__ = "0.1.8"
+__version__ = "0.1.9"