Change getAllTools() to return ToolInfo[] instead of string[]

Breaking change: pi.getAllTools() now returns Array<{ name, description }>
instead of string[]. Extensions needing just names can use .map(t => t.name).

Removes redundant getToolInfo() method added in original PR.

Fixes #647

packages/coding-agent/src/core/extensions/index.ts

@@ -99,6 +99,7 @@ export type {
 	ToolCallEventResult,
 	// Tools
 	ToolDefinition,
+	ToolInfo,
 	ToolRenderResultOptions,
 	ToolResultEvent,
 	ToolResultEventResult,