chore: release v0.1.12 (#392)

This PR updates the version to 0.1.12 after publishing to PyPI.

## Changes
- Updated version in `pyproject.toml` to 0.1.12
- Updated version in `src/claude_agent_sdk/_version.py` to 0.1.12
- Updated `CHANGELOG.md` with release notes

## Release Information
- Published to PyPI: https://pypi.org/project/claude-agent-sdk/0.1.12/
- Bundled CLI version: 2.0.58
- Install with: `pip install claude-agent-sdk==0.1.12`

🤖 Generated by GitHub Actions

---------

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>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Ashwin Bhat <ashwin@anthropic.com>

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## 0.1.12
+
+### New Features
+
+- **Tools option**: Added `tools` option to `ClaudeAgentOptions` for controlling the base set of available tools, matching the TypeScript SDK functionality. Supports three modes:
+  - Array of tool names to specify which tools should be available (e.g., `["Read", "Edit", "Bash"]`)
+  - Empty array `[]` to disable all built-in tools
+  - Preset object `{"type": "preset", "preset": "claude_code"}` to use the default Claude Code toolset
+- **SDK beta support**: Added `betas` option to `ClaudeAgentOptions` for enabling Anthropic API beta features. Currently supports `"context-1m-2025-08-07"` for extended context window
+
 ## 0.1.11
 
 ### Internal/Other Changes

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "claude-agent-sdk"
-version = "0.1.11"
+version = "0.1.12"
 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__ = "0.1.11"
+__version__ = "0.1.12"