refactor: tool plugin registry - each tool in separate file

lib/tools/_registry.ts

@@ -0,0 +1,44 @@
+/**
+ * Tool plugin registry.
+ * Aggregates all VoiceTool instances, exposes TOOL_SCHEMAS array
+ * and executeTool dispatcher.
+ */
+
+import type { AgentId, VoiceTool } from './_types'
+import { ToolHttpError } from './_http'
+
+import { tool as weather } from './weather'
+import { tool as transport } from './transport'
+import { tools as calendarTools } from './calendar'
+import { tools as timerTools } from './timers'
+import { tool as notes } from './notes'
+
+const ALL_TOOLS: VoiceTool[] = [
+  weather,
+  transport,
+  ...calendarTools,
+  ...timerTools,
+  notes,
+]
+
+export const TOOL_SCHEMAS = ALL_TOOLS.map((t) => t.schema)
+
+export async function executeTool(
+  name: string,
+  args: Record<string, any>,
+  agent: AgentId,
+): Promise<Record<string, any> | { error: string }> {
+  const t = ALL_TOOLS.find((t) => t.schema.function.name === name)
+  if (!t) return { error: `unknown tool: ${name}` }
+  try {
+    return await t.execute(args || {}, agent)
+  } catch (e) {
+    if (e instanceof ToolHttpError) {
+      return { error: `tool_http_${e.status}` }
+    }
+    if (e instanceof TypeError && /fetch/i.test(e.message)) {
+      return { error: 'tool_network_error' }
+    }
+    return { error: `tool_exception: ${(e as Error).message}` }
+  }
+}