feat(coding-agent): type ToolCallEvent.input per tool

Matches ToolResultEvent pattern with typed inputs via discriminated union.

- Export *ToolInput types from tool schemas
- Add *ToolCallEvent interfaces for each built-in tool
- Add isToolCallEventType() guard with overloads for built-ins

Direct narrowing (event.toolName === "bash") doesn't work due to
CustomToolCallEvent.toolName: string overlapping with literals.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/coding-agent/src/index.ts

@@ -46,10 +46,13 @@ export type {
 	AgentToolResult,
 	AgentToolUpdateCallback,
 	AppAction,
+	BashToolCallEvent,
 	BeforeAgentStartEvent,
 	CompactOptions,
 	ContextEvent,
 	ContextUsage,
+	CustomToolCallEvent,
+	EditToolCallEvent,
 	ExecOptions,
 	ExecResult,
 	Extension,
@@ -69,15 +72,19 @@ export type {
 	ExtensionUIContext,
 	ExtensionUIDialogOptions,
 	ExtensionWidgetOptions,
+	FindToolCallEvent,
+	GrepToolCallEvent,
 	InputEvent,
 	InputEventResult,
 	InputSource,
 	KeybindingsManager,
 	LoadExtensionsResult,
+	LsToolCallEvent,
 	MessageRenderer,
 	MessageRenderOptions,
 	ProviderConfig,
 	ProviderModelConfig,
+	ReadToolCallEvent,
 	RegisteredCommand,
 	RegisteredTool,
 	SessionBeforeCompactEvent,
@@ -100,6 +107,7 @@ export type {
 	UserBashEvent,
 	UserBashEventResult,
 	WidgetPlacement,
+	WriteToolCallEvent,
 } from "./core/extensions/index.js";
 export {
 	createExtensionRuntime,
@@ -111,6 +119,7 @@ export {
 	isGrepToolResult,
 	isLsToolResult,
 	isReadToolResult,
+	isToolCallEventType,
 	isWriteToolResult,
 	wrapRegisteredTool,
 	wrapRegisteredTools,
@@ -196,6 +205,7 @@ export {
 export {
 	type BashOperations,
 	type BashToolDetails,
+	type BashToolInput,
 	type BashToolOptions,
 	bashTool,
 	codingTools,
@@ -203,23 +213,28 @@ export {
 	DEFAULT_MAX_LINES,
 	type EditOperations,
 	type EditToolDetails,
+	type EditToolInput,
 	type EditToolOptions,
 	editTool,
 	type FindOperations,
 	type FindToolDetails,
+	type FindToolInput,
 	type FindToolOptions,
 	findTool,
 	formatSize,
 	type GrepOperations,
 	type GrepToolDetails,
+	type GrepToolInput,
 	type GrepToolOptions,
 	grepTool,
 	type LsOperations,
 	type LsToolDetails,
+	type LsToolInput,
 	type LsToolOptions,
 	lsTool,
 	type ReadOperations,
 	type ReadToolDetails,
+	type ReadToolInput,
 	type ReadToolOptions,
 	readTool,
 	type ToolsOptions,
@@ -229,6 +244,7 @@ export {
 	truncateLine,
 	truncateTail,
 	type WriteOperations,
+	type WriteToolInput,
 	type WriteToolOptions,
 	writeTool,
 } from "./core/tools/index.js";