BREAKING CHANGE: ToolDefinition.execute parameter order changed from
(id, params, onUpdate, ctx, signal) to (id, params, signal, onUpdate, ctx).
This aligns with AgentTool.execute so wrapping built-in tools no longer
requires parameter reordering. Update extensions by swapping signal and
onUpdate parameters.
- Add setActiveTools() to ExtensionAPI for dynamic tool management
- Extensions can now override, wrap, or disable built-in tools
- Add tool-override.ts example demonstrating the pattern
- Update documentation for tool override capabilities
